1 East Asia Before the Sino-Japanese War of 1894–95

BeforeFootnote 1 the Sino-Japanese War of 1894–95, China was the dominant power in East Asia. Its overwhelming presence can be clearly seen just by looking at its vast territory and huge population. Moreover, there existed a regional order in East Asia with the Chinese dynasty at the apex and center, and until the eighteenth century, the international order of Europe and the East Asian order coexisted as separate entities.

From the mid-nineteenth century onward, with the Opium War and the Second Opium War (Arrow War), the Qing Dynasty was drawn into the international relations of the modern West as Western nations advanced into the region. However, the Qing Dynasty was still the dominant power in East Asia. This was true both in its own consciousness and in the eyes of Western nations.Footnote 2 The Sino-Japanese War of 1894–95 changed such status of the Qing and the regional order in East Asia.

In Japan, the Meiji Restoration led to the formation of a central government, the abolition of domains and the establishment of prefectures, and the delineation of territories. The Meiji government took over the treaties that the Edo shogunate had concluded with foreign countries and sought to revise them (see Chap. 4, Sect. 4.3, “Japanese Meiji Restoration and Modernization”). Japan proceeded to form a modern nation state and attempted to establish relations among nations based on modern Western principles.

Such efforts to form a modern nation state in Japan clashed with the East Asian order, especially China. For example, in the 1870s, the Meiji government incorporated the Ryukyu Kingdom as a Japanese territory, making it Okinawa Prefecture. Originally, during the Edo period, the Ryukyu Kingdom paid tribute to the Qing Dynasty while being ruled by the Satsuma clan, which was part of Japan. The Meiji government severed the relationship between the Ryukyu Kingdom and the Qing, abolished the Ryukyu Kingdom, and made the Ryukyu Islands a distinctly Japanese territory.

Japan also forced Korea to open its doors to the outside world and concluded the Japan-Korea Treaty of Amity (Treaty of Ganghwa Island) in 1876. In the first subsection of the treaty, Korea was positioned as an independent country with equal rights with Japan. The Qing Dynasty positioned Korea as a dependent state, while Japan claimed that Korea was an independent country in order to deny it. Such stances continued until the Sino-Japanese War of 1894–95.

The Qing’s policy toward Korea became more powerful in the 1880s. This was an example of how the Qing, confronted with the advance of the Western countries and Japan, responded by strengthening its control over the periphery of its map and the surrounding countries and regions. In 1882, a military uprising broke out in Korea, including an attack on the Japanese legation in Korea (Imo Incident). In 1884, a coup d’état was staged by the radical liberalization faction within the Korean leadership and the Japanese legation in Korea (Gapsin Coup). In both cases, the Qing quickly suppressed the rebellion and coup militarily. The Qing also took the lead in facilitating the conclusion of the Treaty of Amity and Commerce between Korea and the West. The relationship between the Qing and Korea was based on the traditional relationship of suzerainty and vassalage, but with a strong control that had not been exercised in the past. The Qing tried to make the Western countries accept such a relationship between the Qing and Korea.

Following the Gapsin Coup, Japan and China concluded the Convention of Tientsin in 1885 and withdrew their troops from Korea. The treaty also stipulated that they would notify the other side in advance if there was a disturbance in Korea in the future and they sent troops to Korea. Although Korea did not welcome the Qing’s growing influence over Korea and sometimes made attempts to approach Russia, it did not intend to deny its position as a dependent state of the Qing. Also, Western countries did not seek to expand into Korea at huge cost. The countries concerned recognized the dominant position of the Qing in Korea and acted on that basis.Footnote 3

Japan, too, had avoided confrontation with the Qing since the Gapsin Coup and had in effect tacitly accepted the Qing’s dominance in Korea. However, it did not want the Qing’s influence to be decisively strengthened in Korea. In addition, Japan did not change its policy of treating Korea as an independent country. Japan and China maintained peaceful relations for a while, leaving the seeds of a conflict over Korea untouched.

2 The Sino-Japanese War of 1894–95

For Japan’s foreign policy during and around the Sino-Japanese War of 1894–95, see Sasaki (2017, 2022a). See also Paine (2003) and Zachmann (2005).

In 1894, a popular uprising broke out in Korea and grew in scale from April to May. In early June, the Qing government decided to accept a request from Korea to deploy troops in order to suppress this uprising. At the same time, Japan also made preparations to deploy troops in the name of protecting the Japanese legation and Japanese people in Korea. At the time of the Imo Incident and the Gapsin Coup, the Qing had quelled the civil unrest in Korea and strengthened its influence. Japan wanted to avoid a similar turn of events again, and thought it was important to dispatch as many troops to Korea as quickly as possible without falling behind the Qing.

However, the rebellion had already begun to subside when some of Japan’s troops arrived in Korea. But Japan could not accept the withdrawal of its troops at this point. This is because the Qing had dispatched its troops at the request of Korea, and the Japanese troops were deployed for the reason of protecting the Japanese legation and Japanese people in Korea. As such, if both the Qing and Japanese troops were withdrawn without any particular action, only the record of the Qing’s dispatch to Korea in the name of protecting the country would remain.

Japan proposed to the Qing that they should jointly reform the internal affairs of Korea while keeping their troops in the country. However, the Qing, which regarded Korea as a dependent state and held a dominant position in the country, would not agree to this. Korea also refused to accept Japan’s demand for internal political reform and repeatedly asked Japan to withdraw its troops. The reform of internal affairs means the development and improvement of various systems such as politics, law, military affairs, finance, police, and transportation. In this case, it was meant to weaken Korea’s relationship with the Qing by taking measures to strengthen Korea.

At the request of the Qing, Russia and Britain mediated, and there were times when it seemed that a military conflict between Japan and the Qing could be avoided. However, in the end it was difficult to create a solution that would satisfy both Japan and the Qing. Japan and the Qing were at odds on the fundamental question of whether Korea was a dependent state of the Qing or an independent state, and for the reasons mentioned above, Japan could not withdraw its troops without any positive outcome on its part.

Diplomatic negotiations between Japan and the Qing failed to reach an agreement, and the Sino-Japanese War began in late July. By September, Japan had gained the upper hand and was dominating the war, and the Japanese forces continued to win each battle thereafter. Japan’s military was small until the 1870s, but from the 1880s, it began to expand its armaments in order to compete with the might of the Qing. The Qing, on the other hand, had problems in terms of military training and discipline, and did not have a system for waging war as a whole nation. Japan wiped out the Qing forces in Korea, secured control of the seas, captured the Liaodong Peninsula, Weihaiwei, and the Liaohe Plain, and then prepared for the final battle near Beijing.

In April 1895, Japan and the Qing Dynasty signed a peace treaty (Treaty of Shimonoseki). In this treaty, the Qing recognized Korea as a fully independent country, and the pre-modern order in East Asia, centered on Chinese dynasties, collapsed. The treaty also provided for the cession of the Liaodong Peninsula, Taiwan and the Penghu Islands, the payment of 200 million ryo in reparations, and the conclusion of a treaty of commerce and navigation between Japan and China based on similar treaties that the Qing had signed with European countries. With regard to the Liaodong Peninsula, as a result of the Triple Intervention initiated by Russia, France, and Germany, Japan promised the three countries that it would renounce its claim on this area. In November, the Convention of Retrocession of the Liaodong Peninsula was concluded between Japan and the Qing, under which Japan would return the Liaodong Peninsula to the Qing and the Qing would pay Japan 30 million ryo. The total amount of reparations and additional compensation was more than four times the annual national budget of Japan before the Sino-Japanese War.

In Korea, just before the outbreak of the Sino-Japanese War, Japanese troops surrounded and occupied Korea’s royal palace, inaugurated a new government, and severed ties with the Qing. Japan then adopted a policy of supporting the independence of Korea and promoted the reform of its internal affairs. In some respects, the policy was carried out with the recognition of its necessity within the Korean leadership. However, Japan also hoped that the reform process would strengthen ties between Japan and Korea through the hiring of advisors, loans, and introduction of technology, and expand Japanese influence and interests in Korea.

But the idea of domestic policy reform, in which Korea relied on Japan to promote its modernization policy, was impossible to begin with. Generally speaking, reforms are invariably met with opposition. Moreover, Japan had sent troops to Korea to fight against the Qing and supported or forced the reform of Korea through military power. It was only natural that there would be a backlash in Korea against Japan and domestic reforms. Once again, a large-scale popular uprising broke out, which was suppressed by the Japanese and Korean armies. In addition, Japan had not been able to establish a stable partnership with the king and government of Korea.

After the Triple Intervention, there was a tendency in Korea to rely on Russia instead of Japan. The Japanese side believed that Queen Min was taking the lead in promoting a pro-Russian and anti-Japanese policy, and in October 1895, Queen Min was assassinated with the involvement of the Japanese Minister to Korea. Japanese involvement was exposed from the beginning, partly due to a miscalculation, and the Japanese government declared to the rest of the world a policy of non-interference by Japan in Korea. The political situation in Korea continued to be unstable, and finally, in February 1896, King Gojong of Korea sought refuge in the Russian legation, and the growth of Russia’s power in Korea and Japan’s decline became conclusive. The Japanese government made an agreement with Russia to stabilize the situation in Korea and refrained from involvement in Korea.

3 East Asia After the Sino-Japanese War

For this section, see Sasaki (2017, 2022c). See also Malozemoff (1958), Duus (1995), and Otte (2007).

After the Sino-Japanese War, the East Asian world changed dramatically. As a result of the peace treaty, Japan acquired Taiwan and the Penghu Islands, which became the starting point for Japan’s subsequent expansion. In addition, Japan received significant reparations, most of which was invested in its military expansion. In the Sino-Japanese War, while the Qing did not have a powerful modern army and nor did it fight with all its strength as a nation, Japan fought with almost all its forces. Then came the Triple Intervention, and Japanese leaders feared that the Three Powers might use force if necessary and felt threatened by the inadequacy of Japan’s defense. The Sino-Japanese War made Japan’s leaders realize that its military was still inadequate. As a result of this military expansion, war with Russia later became a realistic option for foreign policy within the Japanese government.

On the other hand, the international reputation of the Qing declined. The Qing had often sought the intervention of the major powers in the war, and in fact, it was able to regain the Liaodong Peninsula through the intervention of the Three Powers. It also needed to raise funds from European countries to pay reparations to Japan. As a result, it was subject to further incursions by European powers. The Qing Dynasty fell from its position as a great power in the East, and China became a major focus of international politics as an arena or an object. The catalyst for this was the Sino-Japanese War.

In November 1897, Germany occupied Jiaozhou Bay on the pretext of the murder of a German missionary in China, and after negotiations, signed a treaty with the Qing in March 1898 to lease Jiaozhou Bay for 99 years. In March of the same year, Russia signed a treaty with the Qing to lease Port Arthur and Talien. The term was 25 years. Britain, France, and Japan joined in the movement. This was the so-called partition of China. It did not mean that the territory of China was really divided, but that European powers and Japan attempted to expand into China in various ways, such as through leasing, acquisition of various interests, and demands for non-cession of territory to other countries.

In Korea, the king returned to the royal palace in February 1897, the Korean Empire was established in October, and opposition to Russia became apparent. At the same time, Russia was in the process of acquiring Port Arthur and Talien as part of the partition of China, and Russia’s interest in these areas was becoming more focused, and Japan wanted to expand its influence in Korea if the opportunity arose while avoiding confrontation with Russia. In April 1898, the Nishi-Rosen Agreement was signed, in which Japan and Russia confirmed Korea’s sovereignty and independence, and Russia recognized Japan’s large commercial and industrial interests in Korea. Although Russia did not completely lose interest in the Korean Peninsula, and potential conflicts existed between Japan and Russia, the two countries created a lull by dividing their interests, with Russia going to Manchuria and Japan going to Korea.

4 The Russo-Japanese War

For this section and the Russo-Japanese War, see Okamoto (1970), Wolff (1999), Steinberg et al. (2005), Chapman and Inaba (2007), Kowner (2007a, 2007b), Wolff et al. (2007), Ericson and Hockley (2008), Sasaki (2017, 2022c), and Streltsov and Shimotomai (2019).

The balance between Japan and Russia was shattered by the Boxer Rebellion. As opposition to increasing foreign intervention grew in China, the Boxer Rebellion broke out between 1899 and 1900. The Qing government took advantage of this development, and war between China and the European powers and Japan ensued. The war itself was won quickly by the Allied forces, with Japan and Russia, situated in close geographical proximity to China, dispatching large numbers of troops. However, in the midst of the war, Russia occupied Manchuria and did not withdraw from the region.

Japan signed the Anglo-Japanese Alliance in January 1902 to put pressure on Russia. Although elder statesman Itō Hirobumi was concerned about taking a hardline stance against Russia, Katsura Tarō, who became Prime Minister in June 1901, Foreign Minister Komura Jutarō, and Yamagata Aritomo, who, like Itō, was also an elder statesman, thought that forming an alliance with Britain would be a powerful means to put diplomatic pressure on Russia. And within the Japanese government, the logic that Russia’s occupation of Manchuria would be a serious threat to Korean independence and thus to Japan began to take root. The British were also trying to change their policy of isolation, and their evaluation of Japan and Japanese military power led them to form an alliance with Japan.

In April 1902, Russia concluded an agreement with China concerning Manchuria, and agreed to withdraw its troops in stages. The first withdrawal took place in October, but the second withdrawal, scheduled for April 1903, did not happen. In June, the Japanese government decided to go into negotiations with Russia.

From that point on, negotiations between Japan and Russia continued for some time. The negotiations, however, were structurally difficult to conclude. Prior to the Boxer Rebellion, there were some conflicts between Japan and Russia in Korea, but the two countries were basically divided in terms of where they sought to expand: Russia in Manchuria and Japan in Korea. However, with Russia’s military occupation of Manchuria, such a balancing act between Japan and Russia became untenable. This was because there was a huge difference between Russia’s position in Manchuria and Japan’s position in Korea. From Russia’s perspective, there was no need to negotiate with Japan over Manchuria. On the other hand, negotiating with Russia over Korea only would have weakened Japan’s negotiating position compared to a scenario in which both Manchuria and Korea were the focal points, and Japan would not have been able to reach a satisfactory deal.

Furthermore, as already mentioned, Japan had expanded its military after the Sino-Japanese War, and war with Russia had become a realistic option in terms of foreign policy. And if the war was postponed, the military balance concerning the Far East between Japan and Russia would become more favorable to Russia. Prime Minister Katsura and Foreign Minister Komura made up their minds to initiate the war at an early stage, the idea was then finalized among the Japanese leadership, and the Russo-Japanese War began in February 1904.

The main battlefield was Manchuria, where several large-scale battles were fought. A fierce battle was also fought at Port Arthur. There were many casualties on both sides, and it was not a unilateral victory for Japan. But Japan pushed back the Russian army in each battle on the Manchurian Plain and advanced. It also captured Port Arthur. The Battle of Tsushima in May 1905 was a complete victory for Japan. The Japanese government asked the U.S. to mediate for peace, and peace negotiations were held in the United States.

The Russo-Japanese War was an all-out conflict between military powers with modern land and naval forces. With elements of total war and indirectly involving countries and regions around the world, it is sometimes referred to as World War Zero. Based on the provisions of the Anglo-Japanese Alliance, Britain would remain neutral as long as Japan was fighting against Russia alone, and if other countries took Russia’s side and entered the war, Britain would also enter the war. Therefore, Britain remained neutral, but checked other powers to prevent them from joining Russia and provided support to Japan. The U.S. also showed a favorable attitude toward Japan.

In September 1905, Japan and Russia signed a peace treaty (Treaty of Portsmouth), in which Russia ceded to Japan, with the consent of China, the lease of Port Arthur and Talien, the railway between Changchun and Port Arthur, and related concessions. South Sakhalin was also ceded. Russia also recognized Japan’s dominant position in Korea.

5 Japanese Annexation of Korea

For the annexation of Korea, see Conroy (1960), Duus (1995), and Dudden (2005).

The Russo-Japanese War determined the fate of Korea. Even before the Russo-Japanese War, Japan and Russia were trying to make inroads into Korea, and there were various moves regarding the acquisition of concessions, purchase of land, territorial lease and loan, but the situation was not such that Korea’s status as an independent nation was under threat. However, through the Russo-Japanese War, Korea was quickly brought under Japanese control.

Shortly after the Russo-Japanese War began in February 1904, Japan signed the Japan-Korea Treaty of 1904. This treaty provided for the stable use of the Korean Peninsula by Japan in the war effort against Russia and also placed Korea under Japanese protection. Yet, the content of the treaty was largely abstract, such as that Korea would accept the advice of the Japanese government on improving its administration and that the Japanese government would guarantee Korea’s independence.

Therefore, the Japanese government attempted to conclude further arrangements with Korea. In particular, the Japanese focused on seizing control of Korea’s diplomatic rights and cutting off the possibility of Korea’s becoming associated with any other country besides Japan. In August 1904, the first Japan-Korea Agreement was signed, under which Korea was to engage financial supervisors and diplomatic advisors recommended by the Japanese government and consult with Japanese representatives in advance regarding the handling of foreign relations. In November 1905, after the end of the Russo-Japanese War, the second Japan-Korea Agreement was signed under Japanese military coercion, under which the Japanese government was to supervise and direct Korea’s diplomatic relations and appoint representative superintendents in Korea.

The second Japan-Korea Agreement itself related to Korea’s diplomatic rights, which at that stage differed from the post-1907 system in which Japan took control of Korea’s internal affairs. However, it determined that Korea was to be placed under the exclusive protection and control of Japan. The powers had already recognized Japan’s dominant position in Korea in the Taft-Katsura Agreement (July 1905) with the United States, the second Anglo-Japanese Alliance (August 1905) with Britain, and the Treaty of Portsmouth (September 1905) with Russia.

Up to this point, there had been no disagreement among Japanese leaders about policy toward Korea. Japanese leaders were unanimous in their recognition of the need to maintain control of Korea’s diplomatic rights in order to keep the Korean Peninsula safe for Japan. In addition, “protection” was a multifaceted concept. It was often, in effect, domination or deprivation of state functions, but it also had implications such as support for independence. Supporting the independence of Korea, for example, was something that Itō Hirobumi had advocated since before the Sino-Japanese War of 1894–95.

In his own subjective view, Itō, who became the first Resident-General of Korea, tried to use his own experience of modern nation-building as a leader in Japan to improve the administration in Korea and support Korea’s independence. However, the same problem arose as with the domestic policy reform and modernization measures initiated during the Sino-Japanese War. In other words, reforms are generally met with resistance, and in addition, there was a great deal of opposition to Japan’s military coercion of Korea. Also, a stable alliance between the Japanese government and the Korean leadership had not been established. In 1907, during the Universal Peace Congress in The Hague, the Emperor of Korea sent an envoy to complain about the injustice of Japan’s domination of Korea, which led to the conclusion of the third Japan-Korea Agreement and the strengthening of Japan’s control over Korea in domestic affairs. Even after this, Japan did not achieve control of Korean minds, and the resistance movement was on the rise, leading Itō to approve the annexation of Korea.

Katsura Tarō, who stepped down as Prime Minister after the Russo-Japanese War and became Prime Minister again in 1908, Foreign Minister Komura Jutarō, and Yamagata Aritomo believed that Japan should tighten its control over Korea as much as possible in order to make the Korean Peninsula safe for Japan. If control was strengthened based on such thinking, the end result was annexation. After negotiating with Russia and Britain, Japan annexed Korea in August 1910.

6 Japanese Diplomacy in the Age of Imperialism and Foreign Expansion

For this section, see Iriye (1972), Hunt (1973), Brooks (2000), Murashima (2000), Steeds (2000), O’Brien (2004), Woodhouse (2004), Asada (2010), and Sasaki (2017, 2022b, 2022c).

In December 1905, after the end of the Russo-Japanese War, a treaty was signed between Japan and the Qing regarding Manchuria, in which the Qing recognized Japan’s inheritance of Russia’s interests in South Manchuria. At the same time, Japan also demanded various concessions in South Manchuria. As a result, some of these were accepted by the Qing, but there were many areas where the conclusions remained unclear and were left to subsequent interpretation and power relations. Japan tried to secure and expand its interests to the maximum extent possible in the face of this ambiguous situation. In 1909, for example, it signed an agreement with the Qing on Manchuria and Gando, which collectively settled several issues concerning Manchuria and the border between China and Korea.

Japan also signed the first Russo-Japanese Agreement (1907) and the second Russo-Japanese Agreement (1910), dividing the sphere of influence into North Manchuria for Russia and South Manchuria for Japan. When the Xinhai Revolution broke out in China in 1911, Japan and Russia signed the third Russo-Japanese Agreement in 1912, extending the existing demarcation line westward and dividing Inner Mongolia as well. Japan’s sphere of influence included South Manchuria and eastern Inner Mongolia.

After the Russo-Japanese War, Russia abandoned its expansion into South Manchuria and the Korean peninsula, and Japan and Russia established a partnership. Anglo-Russian relations also improved, and cooperative relationships were established among Britain, Russia, France, and Japan. On the other hand, conflicts began to arise between Japan and the U.S. over such issues as the opening of Manchuria, although these were not necessarily persistent and serious problems at first.

Japan’s territory and influence continuously expanded, starting with the acquisition of Taiwan and the Penghu Islands through the Treaty of Shimonoseki, followed by the acquisition of South Sakhalin and concessions in South Manchuria through the Russo-Japanese War, and the annexation of Korea. This external expansion included not only territorial expansion and the acquisition of colonies, as one might intuitively think, but also the acquisition of rights and interests and the establishment of a sphere of influence, especially in China. There were various patterns of spheres of influence, such as having significant interests, mutual recognition among the powers, or forcing China to recognize non-cession of territory to other countries, and the reality and the degree of subordination differed. For example, although the first and second Russo-Japanese Agreements both used the same line as the boundary of the sphere of influence, the first agreement stated that the two countries would not interfere with each other, while the second agreement allowed the two countries to take necessary measures to protect their interests in the area, which strengthened the nature of the sphere of influence.

The major factor that created such diversity in sovereignty and territory was the mutual checks and balances among powers. Politically, diplomatically, and militarily speaking, imperialism was characterized by foreign expansion and domination and colonization by different ethnic groups, in which military power was used directly or indirectly. However, in the foreign policy of the imperialist era, there was a horizontal relationship between powers, as well as a vertical relationship between the dominator and the dominated, the invader and the invaded. For example, as China was the focus of interest for the powers, countries could not take irregular and extreme actions there. Sending troops to China and occupying an area without any pretext was not acceptable to the other powers, even if China’s opposition could be suppressed militarily. While checking with each other, the powers secured their sphere of influence in a way that was recognized by the other powers.

Japan, as one of the major powers, was aware of the norms of such horizontal imperialist diplomacy and had ideas such as equalizing mutual interests in diplomacy and preparing arguments and justifications when asserting something. However, the Japanese government focused on justifiability among great powers, not on the notion of justice. It was neither fair nor just for the oppressed to see the powers “fairly” gain rights and expand their sphere of influence.

7 The Xinhai Revolution and the First World War

For Japan’s foreign policy from the period of the First World War to the Paris Peace Conference, see Fifield (1965), Lowe (1969), Dickinson (1999), Kawamura (2000), MacMillan (2001), Elleman (2002), Berton (2011), Minohara et al. (2014), Frattolillo and Best (2015), and Minohara and Dawley (2020).

From October 1911, China found itself in a state of upheaval. The Xinhai Revolution occurred, the Qing Dynasty fell, and the government of Yuan Shikai was established. However, there were rebellions and conflicts among the various forces in China, and Yuan died in 1916.

In Europe, the First World War began in July 1914, and Japan entered the war in August on the grounds of the Anglo-Japanese Alliance, occupying the Shandong region of China, where Germany held the Jiaozhou Bay lease, and the German-held South Sea Islands. The Japanese Foreign Minister Katō Takaaki, who led Japan’s entry into the war, attempted to strengthen Japan’s interests in Manchuria by capturing the Shandong region and using its return to China as a bargaining chip.

The Japanese government regarded South Manchuria as an area that had been gained at great cost in the Russo-Japanese War; it was certainly within Japan’s sphere of influence, and the Japanese government had no intention of giving it up. However, the Russo-Japanese Agreement was only an agreement between Japan and Russia, and Japan did not have firm interests in Manchuria based on an agreement with China. In addition, there was a time limit for the South Manchuria Railway and the lease, with the lease expiring in 1923. The Russian concession was granted in 1898, when the term was set at 25 years, and Japan inherited the concession. Although there was the idea that the term could be extended semi-automatically, the deadline was approaching. Then the First World War broke out, and Katō wanted to use the opportunity to strengthen Japan’s interests in Manchuria.

Japan presented China with the so-called Twenty-One Demands, and in May 1915, finally concluded a treaty with China on Shandong Province and a treaty on South Manchuria and eastern Inner Mongolia. Japan obtained the right to dispose of German interests in Shandong and promised to return the Jiaozhou Bay lease on conditional terms, and the time limit for the leases of Port Arthur and Talien and relating to the South Manchuria Railway were extended to 99 years. However, the negotiations were difficult, and due in part to Japan’s military pressure on China, the Twenty-One Demands was condemned by China and the U.S. until later years and was positioned as a symbol of Japan’s unwarranted expansion into China.

The First World War was unexpectedly large in scale and unexpectedly prolonged. As a result, a power vacuum was created in East Asia. In other words, the powers were originally advancing on China while keeping each other in check. However, the European countries were putting all of their energies into fighting the war, and thus their attention and capabilities toward China declined. Therefore, Japan found itself in a position where it could take independent actions in China if it wanted to. In addition, China was in a state of turmoil, and there were many groups within Japan that wanted to take advantage of this and implement radical measures for foreign expansion. The Japanese government did not necessarily adopt such measures, but the pressure and temptation were always there.

Against this backdrop, for example, in 1916, the Japanese Cabinet decided on a policy of encouraging the dissolution of the Yuan Shikai regime in China. Also, in 1918, it provided large loans to the Duan Qirui regime in China. Such large loans tended to lead to the subordination of the regime itself or to the acquisition of significant rights and interests. Furthermore, in the Siberian Intervention conducted with a request from Britain and France, Japan deployed far more troops to North Manchuria and Siberia than it had agreed to with the United States.

Japan ceased such policies of foreign expansion with the end of the First World War. The Hara Takashi Cabinet, formed in September 1918, attempted to change its course from the irregular foreign policy during the First World War to a diplomacy based on cooperation among major powers as before.

8 Paris Peace Conference

The armistice of the First World War was signed in November 1918, the Paris Peace Conference began in January 1919, and the Treaty of Versailles was signed in June of that year. At the Paris Peace Conference, Japan gained the South Sea Islands. Japan, which had entered the First World War and occupied the German-held islands in the Pacific, wanted to take possession of the islands north of the equator and had gained support from Britain and France during the war. In the end, the South Sea Islands were put under mandate of Japan, which was not exactly the same as possession, but it was almost the same result. This was a traditional form of imperialist diplomacy, where promises and agreements between the major powers were valued.

On the other hand, there were conflicts over Japan’s inheritance of Germany’s interests in Shandong. Japan wanted to take over the rights and interests in Shandong, but China demanded that Germany return them directly to China. Japan argued that it had been agreed between Japan and China that Japan would inherit the Shandong rights and interests and then return them to China later, and that China had also received an advance payment on this basis. In response, China argued that it was coerced by Japan into accepting the Twenty-One Demands and the subsequent treaties. Japan argued for its legitimacy based on the existence of agreements and treaties, while China argued from the perspective that it is not right for a great power to impose a disadvantageous arrangement on the oppressed side against a background of military coercion.

On this issue, U.S. President Wilson was critical of Japan’s policies toward China and was sympathetic of China. However, Japan, a major victor along with U.S., Britain, and France, insisted on inheriting the rights and interests of Shandong in a hardline manner, so Wilson had no choice but to accept Japan’s demands. And in the end, a settlement was reached by clarifying the details of the rights and interests that Japan intended to acquire. The Treaty of Versailles provided for the succession of Japan’s interests in Shandong, and China did not sign the treaty.

9 The Changing International Order and Japanese Diplomacy

For the international order and Japanese diplomacy after the First World War, see Iriye (1965), Silberman and Harootunian (1974), Dingman (1976), Waldron (1992), Goldstein and Maurer (1994), Goto-Shibata (1995, 2020), Akami (2002), Asada (2006), Manela (2007), Burkman (2008), Gorman (2012), Shinohara (2012), Dickinson (2013), and Hattori (2021).

As can be seen in developments which took place surrounding the Paris Peace Conference described above, the international order was transformed after the First World War, a war of unprecedented magnitude. There was a global shift in thought and norms. Criticism of military action, imperialism, and foreign expansion increased. Peace and disarmament were demanded, and a trend toward the outlawry of war was born. The idea of national self-determination was advocated. Alliances between major powers and secret diplomacy came to be viewed negatively. The League of Nations (in which Japan became a permanent member) was established, thereby putting in place a mechanism to maintain peace and stability through a permanent international organization.

Needless to say, the real situation did not shift in direct alignment with the sudden change in ideas and norms. Fundamentally, in international relations, it was easier for a major power to assert demands than a minor one. The powers did not line up one after another to give up their colonies and interests. In addition, the League of Nations was weak in its ability to discipline world affairs.

However, the change in thought and norms affected the behavior of each country, region, and group, including the great powers. Even if the powers did not give up their colonies and interests immediately, they had to manage their diplomacy with a sense of criticism for imperialism. They were more cautious than ever about expansionist policies and military actions. Disarmament treaties were enacted, albeit in stages.

In addition to changes in ideas and norms, the power structure of the major powers also changed. As far as East Asia is concerned, first, the United States rose to prominence. In the First World War, the U.S. entered the war on the side of the Allies, including Britain and France, and the Allies were able to win the war. By helping determine victory for the Allies, the U.S. gained a greater voice in international society. Furthermore, while Europe had been devastated by the war, the United States was in no such situation. Also, the United States was influential in terms of morality, as President Wilson announced the Fourteen Points, the principles of the postwar order. From the final stages of the First World War to the ensuing postwar period, the U.S. became the world’s major power in all aspects, including politics, diplomacy, military, economics, and norms. The changes in thought and norms after the First World War were closely tied to the rise of the United States.

Second, the Russian Empire collapsed as a result of the Russian Revolution. It was a little later that the Soviet Union was established as a state and increased its presence, but in terms of ideology and movements, socialism and communism began to have an impact in the surrounding regions and the world immediately after the First World War. Also, as mentioned later, the collapse of the Russian Empire had great significance in China.

Third, China’s role in international society shifted. China entered the First World War on the side of the Allies, became a victorious nation, and joined the League of Nations. The growing criticism of imperialism in the world and the weakening of the system of cooperation among the powers surrounding China also contributed to the strengthening of China’s autonomy.

The above changes in the international order after the First World War also had a major impact on Japanese diplomacy. The Hara Cabinet, which was formed just before the end of the First World War, was trying to abandon aggressive foreign expansion measures that had been developed during the First World War and return to traditional Japanese diplomacy. In other words, it was a return to standard imperialist diplomacy in which Japan’s power and interests were to be developed to the extent that they were recognized by the major powers.

In addition, challenges in coping with the new international order emerged. After the First World War, in the world, the general view of military action, imperialism, and foreign expansion became more critical. The United States, which had become a major world power, criticized Japan’s policy toward China and was wary of Japan’s tendency toward foreign expansion. Also, with the fall of the Russian Empire, Japan lost the partner with whom it had concluded a series of agreements regarding Manchuria and Inner Mongolia. And with the collapse of the Russian Empire and the defeat of Germany in the war, imperialist diplomacy over China became less viable. Aside from Russia and Germany, the other major powers involved in Chinese affairs were Britain, France, Japan, and the United States, but the United States was critical of imperialist diplomacy, in which the powers secured their interests and spheres of influence by checking and cooperating with each other.

In response, the Japanese government refrained from taking advantage of the unstable political situation in China, gradually pulled out its troops from Siberia and tried to compromise with the Chinese side on the Shandong issue. It also took a joint stance with the other major powers on such issues as the elimination of spheres of influence in China.

The Japanese government thus curbed its foreign expansion in many areas and narrowed its focus to a specific region. That region was Manchuria and Mongolia (Manmō), where it sought to protect its interests. Moreover, in the process, it strengthened its resolve and logic for securing Manmō. In other words, the positioning of Manmō as a sphere of influence based on mutual recognition among the powers was insufficient as a basis for justification under new international norms in which imperialist diplomacy came to be viewed critically. Therefore, it was argued that Manmō had a unique connection with Japan, and that Manmō interests were necessary for Japan’s national defense and economic survival. This logic, strengthened by the need to explain the situation to the outside world, guided Japan’s discourse and policy on Manmō.

10 The Possibility of Changing Course?

As we have seen above, the Japanese government adapted to the changes in the international order after the First World War. At the Washington Conference held in 1921–22, the treaty for the limitation of naval armament was signed between the United States, Britain, Japan, France, and Italy. Japan demanded a 70% gross tonnage ratio of its main ships to the U.S., which ended up being 60%, but this was not seen as much of a problem within the Japanese government. Even if the ratio was 60% to the U.S., more importance was placed on establishing the treaty for the limitation of naval armament and avoiding a deepening confrontation with the U.S. Concerning China, the Nine-Power Treaty was concluded, which confirmed such principles as territorial integrity, open door policy, and equal opportunity. Japan’s interests in Manchuria were not denied, and thus it was a treaty that Japan could agree to. In addition, taking advantage of the opportunity of the Washington Conference and with the mediation of Britain and the United States, Japan concluded an agreement with China, and the Shandong problem was thus settled. At the Washington Conference, the Anglo-Japanese Alliance was abolished, but this was not a blow to Japanese diplomacy. For the U.S., the Anglo-Japanese Alliance was undesirable, and Japan did not intend to continue the alliance in the face of strong opposition from the U.S.

However, the Manchurian (Mukden) Incident broke out in 1931. Japan recognized Manchukuo in 1932 and gave notice of withdrawal from the League of Nations in 1933. The Sino-Japanese War began in 1937, the Second World War broke out in Europe in 1939, and Japan entered the Pacific War in 1941.Footnote 4 Japan had been at odds with the international community since 1931 and seemed to have continued on a straight path to war.

This view of the events that took place following the Manchurian Incident is not the mainstream in recent studies. Instead, there is a tendency to emphasize that a variety of potential scenarios were possible. The Manchurian Incident did not immediately and decisively bring Japan into conflict with international society. There was some time between Japan’s notice of withdrawal from the League of Nations and its actual exit. Even after Japan withdrew from the League of Nations, Japan remained within the framework of international cooperation in various fields, and bilateral and multilateral diplomacy existed even if Japan was not a member of the League of Nations. In the case of the Manchurian Incident, the military action itself ceased at a certain stage. And as for the Sino-Japanese War, various efforts were made to resolve the situation.

However, the possibility of such a change in course seems to be an argument that can be made when the situation is viewed in a short-term and limited manner. Based on the historical background and the domestic and international situation of Japan in the 1930s and 1940s, the developments that followed the Manchurian Incident indeed occurred as a chain of events.

First of all, there was a huge gap between Japan’s perception of Manchuria or Manmō and the reality. Through the build-up of historical events that had taken place since the Russo-Japanese War, the Japanese government, military, and public opinion had established that Japan would never give up Manchuria and Manmō. However, Inner Mongolia and North Manchuria were of course not Japanese territory, and neither was South Manchuria. In the latter half of the 1920s, with the advance of the Northern Expedition in China and the rise of the Soviet Union, Japan’s interests in Manchuria became unstable in relation to both China and the Soviet Union. As we will see later, the Manchurian Incident itself was initiated by a part of Japanese soldiers who were out of control, but fundamentally, a structure existed in which the Japanese side had a strong determination to defend Manchuria or Manmō but did not have sufficient grounds to back this. In China and Manchuria, the interests of the powers of the imperialist era remained, while on the other hand, nationalism and anti-imperialism were growing, and various incidents involving Japan occurred, and each time, hardline views were voiced in Japan.

Also, in the 1930s, the military emerged as a significant political force in Japan. After the Washington Conference, Japan was in an era of disarmament, and criticism of the military increased. However, in response to this, arguments were also developed that strongly emphasized the significance of the existence of the military and the importance of national defense and security. A fierce battle of words was waged over the military, with those on the side of condemnation and those on the side of advocacy. Public opinion, as represented by the leading newspapers, was mainly critical of the military in the 1920s, but after the Manchurian Incident, it quickly came to support the military’s logic, advocating hardline foreign policy and encouraging military action. In the midst of this, criticism of the existing political system and ruling class led to frequent terrorist attacks, coups, and attempted coups involving military personnel throughout the 1930s, and the military’s influence was not limited by these incidents, but rather increased. In addition, the Emperor was absolutized, and a tendency arose in which criticism and opposition were not tolerated if the Emperor’s presence was invoked. This was also a factor that increased the power of the military, which was directly subordinate to the Emperor. The system under which the Cabinet, led by the Prime Minister, considered and decided on foreign policy, including the start and end of military operations, was shaken. Although the Meiji Constitution did not institutionally guarantee a parliamentary cabinet system or party cabinets, the political status of political parties had gradually improved, and party cabinets continued from the 1920s to the early 1930s. However, political strife among parties was fierce, and parties and parliamentarians did not unite to block the military’s political advance. The people, too, were dissatisfied and distrustful of the political parties rather than the military, and they did not become more critical of the military.Footnote 5

11 The Manchurian Incident

For the Manchurian Incident, see Ogata (1964), Thorne (1972), Morley (1984), and Nish (1993).

In September 1931, the Japanese troops stationed in Manchuria (the Kwantung Army) blew up the tracks of the South Manchuria Railway and carried out military operations in the name of restoring public order (the Manchurian Incident). In addition, Japanese troops stationed in Korea joined them. They then overran the whole of Manchuria. Aside from the intrigues of the Kwantung Army, the actions of the Japanese Korean Army were also carried out at the sole discretion of the local troops. At the outbreak of the Manchurian Incident, the Japanese government initially adopted a policy of non-expansion. However, this was not achieved, and the situation was allowed to continue.

Japan claimed that the Manchurian Incident was an act of self-defense, and at first the European powers did not condemn Japan. However, as the story spread that the incident was initiated as part of a plot by the Kwantung Army, the Japanese military conducted a wide range of military operations that could hardly be called self-defense, and Manchukuo was established, leading to increased condemnation of Japan. The U.S. was critical of Japan, and in the League of Nations, a number of countries also voiced their criticism.

The League of Nations dispatched the Lytton Commission. While condemning Japan, the conclusions reached by the commission also suggested a compromise favorable to the Japanese. However, Japan was successful militarily, domestic public opinion was upbeat, and the major powers did not condemn Japan or intervene strongly. Therefore, Japan took a hardline stance, acknowledged Manchukuo in September 1932, and gave notice of its withdrawal from the League of Nations in March 1933.

In May 1933, a ceasefire agreement was signed between Japan and China, bringing the hostilities of the Manchurian Incident to an end for the time being. However, the signing of the ceasefire agreement between Japan and China and the further negotiations for conflict resolution and stabilization of the situation did not guarantee stability in the medium to long term. Following the Russo-Japanese War, the area that Japan considered its sphere of influence had been expanding from the Kwantung Leased Territory and the South Manchuria Railway to South Manchuria, and to Manmō, and there were no criteria as to how far this expansion should go before it was brought to a halt. In addition, the Manchurian Incident brought Japan to the option of securing its sphere of influence through the use of military force, which had been planned but never implemented. Even before the outbreak of the Manchurian Incident, conflicts in the region were not uncommon, and of course, after the Manchurian Incident, as the situation became more fluid, problems of this kind occurred frequently. Moreover, the Japanese government was no longer able to fully control military forces on the ground. In Japan, public opinion was leaning toward hardline foreign policy, and the military’s presence and voice as a political force was increasing. The Manchurian Incident did not automatically and inevitably lead to the Sino-Japanese War from 1937; however, the historical background and domestic and international circumstances underlying the Manchurian Incident and the Japanese government’s approval of it led to the Sino-Japanese War followed by the Pacific War.

12 The Sino-Japanese War and the Pacific War

In July 1937, the Marco Polo Bridge Incident occurred, which eventually led to an all-out war between Japan and China.Footnote 6 The battle lines expanded one after another, and China was so vast that no matter how many local battles Japan won or how much territory it occupied, it could not pursue effective military actions further. As the fighting continued, the situation became a stalemate in which neither Japan nor China could militarily determine victory, and political and diplomatic solutions were attempted but never achieved.

On the global stage, the Second World War began in September 1939, and Germany conquered France the following year. Therefore, Japan, wanting to cut off the route of support to China, entered the northern part of French Indochina, where it was easier to advance. And so the Tripartite Pact was signed by Japan, Germany, and Italy. The U.S. imposed economic sanctions on Japan, including an embargo on scrap iron.

In July 1941, Japan occupied the southern part of French Indochina so as to secure resources and cut off further support routes to China. The United States then imposed an oil embargo on Japan. Japan, which was heavily dependent on oil imports from overseas, the lifeline of its war efforts, was forced to make an immediate decision, which led to the outbreak of war with the U.S. In other words, the stationing of troops in southern French Indochina was a major turning point that ultimately led to the outbreak of war with the United States, but at the time of the stationing of troops in southern French Indochina, the Japanese government had by no means resolved to start a war with the United States. It had an optimistic outlook on the American response. The Prime Minister, Konoye Fumimaro, was trying to avoid a war with the United States.

When the situation became quite urgent, Tōjō Hideki, Army Minister in the Konoye Cabinet, became Prime Minister. The army was a major focal point in negotiations with the U.S. However, the negotiations failed to reach an agreement, and in December 1941, Japan attacked Pearl Harbor and the Pacific War began. Japan was engaged in a never-ending war with China, and although Japan had a neutrality treaty with the Soviet Union, the two countries were in a tense relationship that could be severed at any time. It was against this backdrop that Japan went to war against such major powers as the United States and the United Kingdom.Footnote 7

In the beginning of the war, Japan won many battles and expanded its frontiers in Southeast Asia and the Pacific, but it was soon outnumbered, and by 1944, it was in a state of defeat. 1945 saw air raids on Tokyo, the fall of Okinawa, and the surrender of Germany in Europe. In July, the Potsdam Declaration was issued, which called for Japan to surrender. The Japanese government did not accept surrender immediately, but after the atomic bombings of Hiroshima and Nagasaki in August and the Soviet Union’s entry into the war on the side of the Allies, it accepted the declaration. Even after the atomic bombings and the entry of the Soviet Union into the war, the political and military leaders of Japan continued to argue over the terms of surrender, but the Showa Emperor demonstrated his leadership for bringing the war to an early end. Under the Meiji constitutional system, the Emperor in principle exercised his power in a restrained and passive manner, but the Showa Emperor had taken important political actions several times before. And in a situation where political and military leaders were unable to reach a unified decision on the acceptance of defeat, the Emperor’s intervention was necessary. After the acceptance of the Potsdam Declaration, sporadic fighting continued in various areas, and although there were still problems with the repatriation of Japanese troops and Japanese nationals overseas, the document of surrender was officially signed in September.