By any standard the rise of the Scottish National Party (SNP) has been remarkable. Following decades of uneven electoral performance, the party has emerged in the 2000s as the dominant force in Scottish politics, establishing itself as the largest party in the Scottish Parliament and the largest holder of Scottish seats in the UK Parliament, where its forty-five MPs make it the third largest party in the House of Commons. The SNP outperformed its rivals for the fourth consecutive time in the 2021 Scottish Parliament elections and has announced plans for a second independence referendum, which it hopes to hold in 2023. The Scottish Conservative and Labour parties, which dominated Scottish politics for most of the twentieth-century, have fallen distantly behind the SNP, with neither capable of mounting a genuine challenge to it in the last decade.

What explains the ascendancy of the SNP to the top of the Scottish political mountain? In addressing this question, scholars have highlighted a variety of constitutional, political, electoral, and organizational factors. While recognizing the merits of these perspectives, this article takes an explanatory approach rooted in Scotland’s political history. It argues that a key element of the present-day success of the SNP is to be found in the nature of Scottish parties’ past relationships to Scottish society. Drawing on conceptions of political linkage and collateral organizations from political parties’ literature and utilizing party documents, including the papers of the SNP Executive Committee available at the National Library of Scotland (NLS) (Acc. 11987) and materials in the SNP library at the party’s headquarters, as well as some fifteen semi-structured interviews with current and former SNP and Labour party officials, trade union leaders, and interest group representatives, conducted in person or remotely between 2018 and 2022,   the article highlights the outcomes of a set of key debates and developments within the SNP in the 1970s. This was a crucial period in which the party sought to transform itself from a fringe movement with little chance of obtaining political power to a modern party that could viably contest elections. Part of this effort included attempts to anchor the party in Scottish society and establish integrated links with organizations that could provide it with durable mass support, much as its Tory and Labour rivals had done earlier. This effort proved largely unsuccessful and contributed—in the near term—to deepening discord within the party, characterized by the rise of internal factions and external irrelevance, as the party saw its electoral support plummet after 1979. In the long-term, however, the party’s inability to establish these links would actually help create conditions for its later ascendency, allowing the SNP to re-establish itself as a centrist catch-all party better positioned by the 2000s than its rivals to appeal to a wide array of Scotland’s increasingly de-aligned electorate. The article finds that the SNP proved to be—inadvertently—a party ahead of its time.

Patterns of electoral success in Scotland

The decades since the Second World War have been marked by three broad periods of party dominance in Scotland. The first in the 1950s was characterized by the success of the Scottish Conservative (then the Scottish Unionist) Party, whose performance in three consecutive general elections in the 1950s helped propel the UK Tories to 13 years of uninterrupted government control. Labour ascended to the top position in the longer second period, which ran from 1964 until 2010. In every general election in that period, Scottish Labour obtained a greater vote share than any other party, and never held fewer than 56% of Scottish seats at Westminster. Scottish MPs held several high-profile ministerial positions in Labour Governments, including, most notably, the office of Prime Minister, occupied by Gordon Brown, MP for Kirkcaldy and Cowdenbeath, from 2007 to 2010.

The third period has been marked by the overwhelming electoral achievement of the SNP. The party’s success in gaining seats at Westminster had been scant since its “breakout” in the 1974 general elections, when it obtained nearly 30% of the Scottish vote while increasing its MP delegation from one to 11. In the six general elections held from 1979 to 2001, the SNP never held more than six of Scotland’s 72 parliamentary seats. While its seat share increased following the redrawing of Scotland’s constituencies in 2005 and the decline in Scottish MPs from 72 to 59, the party still obtained less than 10% of the Scottish seats in the 2005 and 2010 UK parliamentary elections.

Everything would change with the 2015 General Election, when the SNP captured a stunning 56 of 59 seats, leaving Labour, the Tories, and the Liberal Democrats with only a single MP each. The SNP vote share in the election jumped a remarkable 31% from its 2010 share, with the party obtaining 50% of total Scottish votes. Although the SNP dropped to 35 seats and 37% the vote share in the snap election called by Theresa May in 2017, it rebounded in 2019, claiming 48 seats and 45% of the vote.

The table below documents the vote and seat shares for the four major parties in Scotland in the UK general elections between 1945 and 2019.

A similar shift to the SNP has been evident in the Scottish Parliament, where the SNP’s ascent began nearly a decade earlier than at Westminster. Under the mixed additional member electoral system adopted for the Parliament, the SNP has managed to maintain uninterrupted control over the devolved Scottish government since 2007 and since 2011 has garnered a vote share greater than the combined share of the Tories and Labour in the constituency votes and nearly as great on the regional lists.

Explaining the SNP’s success

Interest in explaining support for the SNP extends back to the party’s initial surge of electoral success that began in the 1960s (Hanham 1969; McLean 1970) and continued in the 1970s (Jaensch 1976; Brand 1978). The party’s more recent—and more dramatic—electoral triumphs have likewise elicited a range of proposed explanations. An obvious starting point for explaining the SNP’s success in the 2000s involves the rising share of Scots in favour of an independent Scottish state. Yet SNP and independence support have not always tracked one another. In 2007, when the party first bested Labour to win a plurality of the vote share in the Scottish Parliamentary elections, support for independence was actually lower (24%) than in 1999 (27%), when Labour beat the SNP by 10%. And while support for independence stood at 39% by the time of the 2015 UK General Election, this figure was still only 4% higher than the comparable figure in 2005, when the SNP earned only 6 seats on a 17.7% vote share (Curtis 2016, p. 5; House of Commons Library 2021; Scottish Parliament 2021).

While heightened levels of independence support alone may not explain the SNP’s success, it is possible that the party increased its vote share by consolidating the votes of independence backers. Johns and Mitchell (2016) argue that a rising number of voters came to see constitutional questions as crucial for their voting intention after the referendum, and overwhelmingly cast ballots for the SNP in 2015, even, as the authors point out, when their specific constitutional preferences (such as greater powers for the Scottish Parliament within the union) better matched the policy positions of a different party. Fieldhouse et al. (2019) make a similar claim, arguing that the independence referendum was an electoral shock that altered the basic political alignments in Scotland by making it difficult for independence supporters to reconcile voting yes in the referendum with supporting a unionist party in the general election. As constitutional issues grew in importance to voters, the SNP’s success was clearly facilitated by the presence of a first-past-the-post electoral system for Westminster and its partial use for Holyrood. Despite more Scottish voters choosing Labour, Tory, or Liberal Democratic candidates in the 2017 and 2019 General Elections and the 2021 Scottish Parliament election, the SNP nevertheless triumphed easily because the Unionist constituency votes were split three ways.

Perspectives on the SNP’s rise in the 2000s and particularly its victories in 2007 and 2015 have also focused on the changing constitutional and political context in Scotland after 1999 and the party’s responses to these changes. Bennie (2016, p. 22) traces the relationship between devolution and the SNP’s successes at both Holyrood and Westminster, arguing that the creation of the Scottish Parliament was “the catalyst” for the party’s growth. Mitchell et al. (2012, p. 1) also cite the importance of the constitutional changes in the 1990s for the party’s 2007 victory, but additionally emphasize changes within the party, arguing that an organizational evolution took place in the early 2000s through which the SNP had developed a pragmatic policy agenda, a clear centre-left orientation, and—in contrast to the other Scottish parties—a growing bloc of members who could provide financial backing and candidates for campaigns. Camp similarly highlights factors internal to the party in explaining its success in Scottish Parliament elections, but notes that the SNP also improved its organization in the 1990s with no obvious electoral benefits at the time. Instead, she emphasizes a combination of organizational improvements and the adoption of more efficient electioneering methods by 2007, including “post-modern” tactics such as the use of websites and computerized databases with voter profiles and contact information (2014, p. 5).

Valence models emphasizing the perceived competence of the SNP once it took office have also been invoked in explanations for the party’s success. Johns et al. (2013, p. 175), for example, describe the 2011 Scottish Parliamentary election, as “a clear case of what has been dubbed “performance politics’… Voters elected an SNP majority government because enough of them deemed the party likelier than its rivals to do a good job in office.” Combined with a Scottish Labour Party in decline and a growing perception that the SNP alone among Scottish parties would “stand up” for Scottish interests in the UK, the SNP’s performance in office after 2007, they argue, helped to lead the party to its majority victory in 2011.

A historical perspective

These explanations provide much that is helpful in understanding the SNP’s successes in the 2000s. Yet they reflect a tendency to view the party’s development as an electorally- relevant force in Scotland in terms of three distinct and disconnected eras, with the first covering the party from the 1960s through its losses in the 1979 General Election, the second its “wilderness years” of mediocre electoral performances in the 1980s and 1990s, and the third beginning with the party’s “rebirth” after the creation of the Scottish Parliament in 1999. For this periodization, developments in each era are frequently viewed as disconnected from one another, with their end dates serving as moments at which politics were seemingly restarted afresh for the SNP.

This article, by contrast, argues in favour of a historical perspective that looks across these temporal boundaries to developments before 1979 that would help make possible the SNP ascendency after 1999. Histories of the SNP have examined the party’s evolution in the 1960s and 1970s, highlighting in particular the growth in party membership, the formulation of detailed policies, and the contesting and winning of elections at both the national and local levels (Brand 1978; Lynch 2013). In many ways, however, the most enduring legacy of this period involved not what the party accomplished but instead what it did not achieve. The capacity of the party after 1999 to respond to external conditions and to make internal adjustments emphasized in the explanations discussed above were facilitated by the fact that the SNP—unlike the main UK political parties in Scotland—never became strongly linked to organizational actors in Scottish society. This absence of organizational linkage was in some instances the result of calculated decisions by the party leadership but in others it resulted from an inability of the party to create it, despite deliberate efforts. The SNP would find itself as a consequence of this “unlinked” status uniquely positioned among Scottish parties to capture by the 2000s an increasingly de-aligned Scottish electorate.

In considering the SNP’s relationship to Scottish society this article draws on the concept of political linkage in comparative literature on political parties. According to Poguntke, parties can create links to voters in two primary ways. First, they may seek to communicate with them directly through different forms of media, political marketing, and mass communication, adjusting their policies to suit preferences identified among voters; second, they may aim to connect to voters through organizational mediators, which “select and aggregate relevant grievances into reasonably coherent packages of political demands” (2002, p. 45). The policy choices and ideological positioning for a party that is organizationally linked are thus determined not by party leaders alone, but in tandem with organization members.

While the direct type of linkage is more closely associated with newer political party types, such as Green parties, organizational linkage served as a key component of the mass party model that dominated the West European party system into the 1960s. In this era, large parties were structured primarily around countries’ core socioeconomic cleavages, and intermediary organizations were often a critical source of durable political support. Successful electoral campaigns for mass parties frequently depended more on mobilizing a party’s established constituencies than winning new converts. Intermediaries—whether a party’s own membership bodies or “collateral” groups formally external to the party itself—could also provide both leaders and rank and file members and even shape a mass party’s basic identity and culture. Among the key collateral groups in this respect were organized religion for centre-right parties and organized labour for centre-left parties; both groups served as crucial social bases for their respective political allies during the twentieth-century (Wren and McElwain 2007).

European party systems have undergone significant changes since the 1960s and parties no longer conform to the mass party model. The factors driving this shift are varied and complex, but include the economic growth of the 1950s and 1960s, the rise of the post-war welfare state, secularization, technological advances, and greater social mobility, all of which helped to erode the sharp social boundaries and collective identities that served to define the mass party era (Wren and McElwain 2007, p. 568; van Biezen and Poguntke 2014, p. 206; Mainwairing and McGraw 2019, p. 676).

These developments also weakened the durable and dependable connections with a small number of large-scale organizations that anchored parties in society. As van Biezen and Poguntke write, “the traditional, almost exclusive reliance of mass parties on specific collateral (religious or trade union) organizations was replaced by a more contingent and instrumental relationship to a larger variety of interest groups characterized by weaker and less regular party ties” (2014, p. 206). Such relationships characterized the catch-all party model, in which leaders displayed increasing authority and autonomy from societal groups and could more freely adapt a party’s ideological and policy orientation in an effort to garner votes from across the socio-economic spectrum (Kirchheimer 1966; Poguntke 2006). The emergence of the catch all party would be associated with a range of broader changes in electoral politics in West European systems, including declining voter turnout, greater electoral volatility, and weaker party identification (van Biezen and Poguntke 2014).

These patterns of change were reflected in the political dynamics of post war Scotland. As parties organized largely—though not exclusively—around the country’s socio-economic cleavage, the Scottish Labour and Tory parties demonstrated the basic features of the organizationally-linked, mass party model. Although neither party had a mass membership organization of the type seen in countries such as Sweden and Germany,both parties relied on deep links to collateral organizations for their success. As the sections that follow detail, it was the Scottish Tories’ relationship with the Protestant churches—and the Church of Scotland in particular—that helped them to mobilize the voters (frequently across class-lines) that propelled their run of electoral triumphs in the 1950s, while Labour’s deep and long-standing connection to Scottish organized labour and specifically the Scottish Trades Union Congress (STUC) was a crucial component of the party’s decades-long electoral reign.

For many in the party leadership in the late 1960s and 1970s, the SNP’s core objective of capturing a majority of Scottish seats in Westminster and demanding from the UK Government a Scottish Parliament with full control over Scottish affairs necessitated that it also aspire to the mass party model, including creating the same types of links to organized actors in Scottish society that the other parties held. For reasons discussed below, this effort ultimately failed to produce the desired outcome and the SNP would enter the 1980s effectively as disconnected from Scottish society as it had been in the 1960s. Yet this lack of linkage would actually help to facilitate the rise of the party in the 2000s.

Collateral organizations: the Scottish Conservative and Labour parties

The Scottish Conservative and Labour parties both experienced periods of electoral dominance in the post war decades, with Scotland’s primary religious and trade union bodies serving as organizations linked to their respective party allies. The strength of these links was such that to some observers post war Scotland resembled a “semi-pillarization” model of the type witnessed in countries such as the Netherlands, “with class and religion and the associated organization and group structures forming the mainstays of support for the main parties” (McTavish 2016, p. 59). The dynamics of these links for each party is explored below.

Conservative linkages

The Tory electoral sweep of the 1950s was rooted in support not only from traditional middle-class voters, but also a large section of the working class with ties to the Church of Scotland. The Church of Scotland was arguably the most significant collateral intermediary of the Tory party during this period, but it was not the only one. Conservatives held long-standing ties to Scottish heavy industries that dominated employment in the country into the post war era. This close relationship would deteriorate as these industries would lose their place in Scotland’s economy, upended by the rise of the service sector and branch-plant manufacturing frequently with foreign ownership (see McTavish 2016). The Kirk’s influence in the country reached new heights in that decade, with some 46% of Scots reporting a formal connection with the Church in 1956, close to the peak connection level of 51% registered in 1905 (Walker 2012, p. 593). In the 1950s, Brown writes, “Scotland remained in the grip of a puritan culture moulded by its Presbyterian heritage” and the Church viewed its greatest challenge at the time, “not in secularism but in other religions, and especially Roman Catholicism” (1997, p. 1).

The links between the Scottish Tories and the established Church were particularly strong during this period; the Church of Scotland, Kidd (2012, p. 63), writes “resembled the Scottish Conservatives at prayer,” and members of the Tory party regularly sat on its Church and Nation committee, which had been founded in 1919 to represent the Church’s views on various political and social issues (Brown 1991, p. 601). This connection was critical for the post war electoral success of the Scottish Tories, which was driven largely by the party’s ability to win working class Protestant voters who still shared a British sense of national identity, with the Protestant faith, Orangeism, and unionism at its centre (Kendrick and McCrone 1989, p. 595).

The organizational linkage between the Scottish Tories and the Church of Scotland continued to provide the party with electoral rewards into the first half of the 1960s. Around this time, however, a set of social and cultural changes would weaken the organizational foundation of Tory support in the country. Foremost among these was a remarkably swift and widespread experience of secularization; by 1963, public participation in religion fell to its lowest level in the century (Brown 1997, p. 1). This decline would continue for the next four decades, with religion becoming less determinative of voting behaviour in Scotland, particularly among Protestants (see Field 2001; Finlay 2004). These developments would hold profound electoral consequences for the Tories.To be sure, Scotland’s secularization was not the sole cause of the Tory decline in the country; the failure of the party to adapt to changing socio-economic conditions, recruit effective leadership, and distinguish itself from the increasingly unpopular UK party after the 1960s were also crucial. Nevertheless, seen first among the traditionally Tory middle classes, the declining Conservative vote share was accelerated by a deterioration in the party’s working-class support, particularly in the west of Scotland, which benefitted Labour (McTavish 2016; Torrance 2012, p. 37). During this period, Conservatives could not rely on the other major confessional group to make up the difference; although Scotland’s Roman Catholic minority maintained comparatively higher levels of church affiliation in these decades, its historically weak enthusiasm for the Tories persisted (Bennie et al. 1997, p. 114).

Beyond the effects of secularization on support for the Scottish Tories were changes in the attitudes of the Kirk itself, which had begun, Finlay writes, “to reflect the more leftist and socially aware attitudes of society in general” (2004, p. 287). For the Tories, this meant they would frequently find themselves on opposite sides from the Church on major issues in the post war period, such as devolution and decolonization (Hutchison 2001, p. 102; Walker 2020, p. 326). This split would become particularly pronounced during the Thatcher years, when the Church made clear its opposition the individualist, laissez-faire orientation of UK government policies. Overall Scottish support for the Conservatives plummeted during the Thatcher/Major governments, falling from 22 seats in the 1979 General Election to zero in 1997 when New Labour ended the Conservatives long reign at Westminster.

Labour linkages

The clearest beneficiary from the changes into the 1960s was the Labour Party in Scotland, which would dominate Scottish electoral politics for the next four decades. As Knox writes, “with the destruction among potential supporters of previously strong ideological and religious barriers, Labour, enjoying mass support, began to reconstruct Scotland into a kind of political fiefdom” (1999, p. 300). Labour certainly benefitted from fortunate timing. The collateral organizations to which Scottish Labour held its most durable links—namely Scottish trade unions—were growing in members and influence in the 1960s and 1970s just as involvement in the Church of Scotland was declining. As Hutchison (2001), notes, this growth held two consequences for Scottish Labour: “first, [the party] retained in a more intact form its core institutional support base, namely the unions… Secondly, the rise of union membership of course meant a great accession of cash and assistance for the party” (136).

Labour relied almost exclusively on its trade union connections for financial and electoral support during this period, with little backing coming from individual members, who were at any rate too few in numbers to make such provision. A “paradox” of Labour cited by Hassan and Shaw (2012, p. 229) was the fact that during its decades of success in Scotland it was never a mass membership party. Of the ten regions into which the UK Labour was segmented, party membership in Scotland was the lowest and had been in decline since the 1950s. In this way, Labour differed from the social democratic party class model, which viewed its membership as the primary source of establishing a common political identity and linking the party to society (see Hassan and Shaw 2012, pp. 229–230). Yet the party did not need a large membership to be successful: Scottish trade unions could serve as an “alternative” to mass membership (236).

Not only were affiliated trade unions represented in all sections of the party, but union organisation assumed an autonomous form in Scotland. The influential Scottish Trades Union Congress, to which most unions were affiliated …well into the 1980s had a massive membership… Scottish Labour was always heavily dependent on its union affiliates, with relations between the party and union elites assuming the form of mutual inter-dependence. (Hassan and Shaw 2012, pp. 226–227)

A set of developments over the next few decades would serve to diminish profoundly the benefits of organizational linkage with the unions that Scottish Labour had enjoyed and contribute to its electoral decline in the 2000s. The first was the loss of jobs in the manufacturing sectors that had historically provided the STUC its members. In 1951, 35.9% of employment in Scotland was located in manufacturing but by 2000 this share had fallen to 14.1%. From a high of nearly 1.1 million in 1980, STUC membership fell to just under 690,000 in 1997, with overall unionization rates in Scotland likewise falling from 55% in 1980 to 32.5% in 2001 (Hassan and Shaw 2012, p. 7). “The STUC and its affiliates,” Aitken writes, “seemed to be shut out of most of the Scottish economy’s growth sectors and worryingly reliant for its membership on declining traditional industries” (1997, pp. 285–286).

In this wider context, the STUC and Labour would begin to diverge in terms of policy, strategy, and—ultimately—linkage. The presence of a common enemy in Tory Governments helped to hold the two together during the long period of Conservative rule in London between 1979 and 1997, but the relationship would face deep challenges with the introduction of New Labour and the emergence of Tony Blair as the national party leader in 1994. While Blair’s centrist approach may have opened new electoral opportunities for the party in England, the policies of the “old” Labour continued to be popular in Scotland. The perception in Scotland of Labour as a party that defends working class interests plummeted in Blair’s first years as prime minister, falling from 97% in 1997 to 53% in 1999 (Lynch 2009, p. 631). Antagonism to trade unions in Scotland was less marked than in England and many Scottish union leaders, Irvine writes, “privately denounced Blair as a Tory” as the STUC increasingly felt its concerns were ignored under New Labour (2004, p. 225). Although union leadership in Scotland in the 1990s continued to be dominated by Labour Party members, these figures were seen by many rank and file members as disconnected and subservient to the UK party in London (interview with former trade union official, 2021).

By the time the Scottish Parliament opened in 1999, the ties had kept trade unions linked with Labour had begun to fray. Increasingly, the unions adopted a more issue-based approach to politics that involved reaching out to other Scottish political parties, including the SNP. Into the 1990s, the relationship between the STUC and the SNP was, in the words of a former trade union official, “hostile to non-existent,” but as Labour’s support in the country softened in the early 2000s and the number of union members favouring independence increased, many in the STUC were willing to rethink their position (interview with former trade union official, 2021).

By the 2007 Scottish Parliamentary elections, the party had lost the support of several key STUC affiliates, including the public sector unions PCS Scotland and Unison, and was struggling win the backing of the STUC General Council. Although Labour ultimately gained the council’s endorsement (by a single vote), a clear message had been sent. As then-deputy SNP leader Nicola Sturgeon commented: “This is a watershed moment in Scottish politics. Labour no longer have anybody’s vote in their pocket” (quoted in McMahon 2007). Labour’s loss in the 2007 election would mark the beginning of the end of the party’s electoral dominance in Scotland.

Collateral organizations: the SNP

At the beginning of the 1960s, the SNP was largely a fringe party with few members, no coherent policy platform outside of Scottish self-government, and no links to the organizations of Scottish society. A member who joined during this period and later served as a party officer recalled how all the delegates at a party conference in Stirling in the early 1960s could fit on the steps in front of the Grand Lion Hotel for a photo (interview with former SNP official, 2018). This situation would soon change. The stunning by-election victory by SNP candidate Winifred Ewing at Hamilton in 1967 revealed a new enthusiasm for the party, particularly among a younger group of university-educated and left-leaning activists who had become disillusioned with the Labour Party following Prime Minister Harold Wilson’s decision to maintain the UK Polaris nuclear deterrent and its submarine fleet based at Holy Loch (interview with former SNP official, 2018). By the start of the 1970s, the SNP had developed considerably as a political party organization, with a large influx of new members, a new generation of leaders, and increasing electoral support. With the discovery of oil in sections of the North Sea to the east and north of Scotland’s coast, the party also found a major new platform upon which it would base much of its economic case for independence in the decade.

The party achieved its first general election victory in 1970, when Donald Stewart won the contest for the Western Isles seat at Westminster but the SNP’s real breakthrough occurred in the two general elections held in 1974. In the February election that year, the party won seven seats on nearly 22% of the Scottish vote share, and increased its seat count in the later October election to 11, with over 30% of the Scottish vote. These successes set off a wave of developments within the party, as leaders came to believe that the SNP was within striking distance of winning a majority of Scottish seats in the UK Parliament, an outcome which, according to party policy of the time, would be taken as a mandate for declaring independence, drafting a new Scottish Constitution, and creating a new Scottish Parliament.

More generally, the efforts of the SNP in this period were geared toward the building of an organization consistent with the model of the mass party. Since its early days following its founding in the 1930s, the SNP had sought to organize itself around the mass model, since its leaders believed that independence could only be achieved if a large part of the Scottish population came to support it. Such a perspective continued into the 1970s, as leaders sought the same objective as their predecessors but now with a growing membership and substantial electoral support (Brand 1978, p. 267). As the decade began, however, the party had very few links to organizations in Scotland and no substantial financing from corporate groups or trade unions (Mullin 1979, p. 116). Funding for the party came largely from the membership via branch events such as jumble sales, beauty pageants, dances, and a type of lottery system of ticket sales known as Alba pools, with additional contributions coming from a handful of wealthy individuals such as Hugh Fraser, chairman of the House of Fraser and Harrods’ department stores (Lynch 2013; Camp 2014).

Linking to the Scottish churches was never really considered by the SNP, despite regional-nationalist parties from areas with distinct religious traditions (such as Scotland) frequently making such connections. Beyond the diminishing electoral returns that links with organized religion could provide in an increasingly secular Scotland, the SNP was deeply concerned about the potential effects of the country’s confessional divide between Protestants and Catholics on unifying support for independence, particularly in light of the growing tensions in Northern Ireland at that time. As Mullin (1979, p. 111) notes, the SNP had long sought “to distinguish Scottish nationalism from the violence associated with Irish nationals” and was reluctant into the 1970s even to mention Ireland. As late as the 1980s, the view remained that sectarian divisions in Scotland were hurting the party’s electoral prospects (Johns and Mitchell et al. 2016, pp. 35–36).

Instead party leaders focused on gaining support from traditional Labour Party voters and becoming, as Brand writes, “an alternative working-class party in Scotland” (1978, p. 284). There were several components to this strategy. The first involved a change in how the party viewed its political role. To a new generation of SNP leaders, including William Wolfe, who succeeded Arthur Donaldson as party leader in 1969, winning a majority of Scottish seats at Westminster required not simply an appeal to voters for Scottish self-government, but a clearly articulated political ideology and detailed policy positions. This viewpoint expanded within the party following the victories in the 1974 General Elections, after which many members came to see the SNP as, in the words of then-Press Officer Stephen Maxwell, “not merely a vehicle for a broad movement for independence, but…the future government of an independent Scotland” (1976, p. 7). Such a position stood in marked contrast to previous SNP thinking, which held that the party should remain non-ideological, promoting only self-determination and separate Scottish governing institutions, which, following independence, could serve as sites for political debates among whatever partisan alignments were represented.

Under Wolfe, the party would move away from such a neutral stance towards a distinctly left-wing posture and directly challenge Scottish Labour. In 1974, the SNP publicly proclaimed itself to be a social democratic party,and began to promote policies that—using revenues from North Sea oil—were designed to address the problems of Scotland’s working classes (Bayne 1991, p. 53). By then, the party had gone into policy overdrive, establishing a range of policy formulation committees and publishing detailed position statements on issues such as housing, the environment, crofting, defence, and—crucially—economic policy and industrial relations. For this final category, the party envisioned of corporatist-style tripartite bargaining structure for Scotland, with the STUC playing a key role as the peak organizational representative of Scottish workers. As Wolfe wrote to the party’s National Council in December 1974:

I believe that we must examine, more thorough than we have already done, possible structures and procedures for the negotiation and settlement of industrial relations and all other matters presently dealt with by the Department of Employment. It is clear that, basically, the STUC and Employers' Organisations should be involved with Government to secure a national framework of agreement on such matters (Scottish National Party 1974)

The details of this policy were contained in a 1976 party pamphlet, which, alongside a raft of pro-trade union measures, outlined the creation of a new Tripartite Economic Council consisting of representatives from government, Scottish employers, and the STUC, which would meet annually to reach a “National Bargain” that would “provide a framework for collective bargaining at industry and plant level in the forthcoming twelve month period” (Scottish National Party 1976).

This policy reorientation favouring Scotland’s working classes was only part of the SNP’s strategy in winning away support from Labour, which also involved a concerted effort to secure a foothold in the organizations of Scotland’s trade union movement. As Ian Bayne, a key figure in the SNP trade union outreach effort in the 1970s, later wrote of this period:

the party was at a distinct disadvantage in the crucial battle with Labour for working-class votes…; not so much because of its policies…nor even because of the occupational or class background of SNP candidates as because it simply lacked the Labour Party’s strong traditional links with the trade union movement and therefore lacked a powerful focus for spontaneous working-class loyalty (1991, p. 53).

For his part, Wolfe recognized the clear benefits the connection with the trade unions provided Labour, while seeing in them a strategy for SNP. As he wrote in one of his early reports as chairman to the SNP National Council in 1971:

The answer, to make us more effective in the future, lies in the strengthening of SNP membership among organised industrial workers, the organisation and training of such member for action in their factories, etc., and in trades councils and, eventually, in the STUC. This is the Labour Party's power house (Scottish National Party 1971).

The primary party vehicle to achieve this strengthening was the Association of Scottish National Trade Unionists (ASNTU), a special organizational affiliate to the party. Established in the mid-1960s and reactivated under Wolfe in the early 1970s, the ASNTU was, in Wolfe’s words, intended to provide “a flow of ideas from the Trade Union movement into the Party and from the Party into the Trade Union movement” and “to encourage members of the Party to take a full and constructive part in all the normal activities of the Trade Union movement” (1973, p. 152). During this period, the party leadership also moved to enhance its connections to the unions by creating an ‘industrial structure’ fronted by ex-Labour Party member Stephen Butler and by encouraging constituencies and branches to monitor activity among trade unions in their areas (Bayne 1991, p. 53).

From the outset, the effort to create a societal base for the SNP in the trade union movement faced difficulties; membership in ASNTU remained low through the 1970s and penetration into the unions was limited (Brand 1978, pp. 284–285). The SNP’s efforts faced sharp resistance from the Labour Party and particularly senior figures in the STUC (many of whom were Labour Party members), who openly shunned the ASNTU and—to the frustration of SNP officers—successfully prevented it from participating in activities where the party hoped to win adherents. In response, Butler suggested the SNP encourage trade union members to stop paying the political levy that helped to fund the Labour Party and engage in direct attacks against trade union leaders in an effort “to undermine their credibility among their own members” (Butler 1977).

While the SNP leadership was fighting with Labour and the STUC over its trade union outreach, the party was also facing its own internal divisions on the strategy. Despite support from figures like Wolfe and Margo MacDonald (who became the public face of the party when she won the by-election in Govan in 1973), many in the party remained ideologically opposed to furthering ties to the trade union movement (see Lynch 2013, p. 142). By the late 1970s, the strategy had become an issue in larger debates emerging in the party and in particular conflicts between leaders in Edinburgh eager to redefine the SNP as social democratic and MPs in London who were representing traditionally Conservative constituencies (Bayne 1991, pp. 53–54).

By the time Wolfe stepped down as leader following the failure of the Scottish Assembly referendum in March 1979 and the disastrous general election two months later in which the SNP’s seat share fell from 11 to 2 and the Thatcher government was elected, the party was in crisis. Even to its proponents, the election had decisively shown the limits of the trade union strategy. As Butler wrote to the National Executive Committee in June 1979:

The last month has told us many things about politics in Scotland. The most significant point for myself was the apparent desertion of ordinary working men and women from the SNP and back to the labour party. The Party must realise that it has not managed over the last 5 years to convince even those who support us in 1974 that we offer a credible alternative to the traditional ties with the labour party (Butler 1979).

The ASNTU went into voluntary abeyance in 1980 and while some figures closely associated with the trade union movement, such as former MP and STUC representative Jim Sillars, advocated renewing party efforts to connect with the trade unions from leadership positions in the SNP in the new decade, there would be fewer benefits to be gained from such a strategy given the massive loss of jobs in traditional trade union employment sectors. (One in three manufacturing jobs in Scotland was lost between 1974 and 1985 (see Gallagher 1991, p. 105).) The defeats of 1979 were moreover followed by a period marked by deep internal conflicts in the SNP, with new leader Gordon Wilson struggling to control the factions that emerged in their wake. The left-wing “79 Group” led by Stephen Maxwell and Margo MacDonald argued that the party needed to redouble its efforts to appeal to the Scottish working classes by pursuing socialist policies and participating directly in industrial actions, while the more traditional Campaign for Nationalism, led by Winifred Ewing, saw the perceived radicalism of the 79 Group as a threat to the future viability of the SNP and the nationalist movement (Torrance 2009, p. 169). Ultimately, seven 79 Group members were expelled from the party in 1982, and although they were later reinstated, the row weakened the party, contributing to its poor performance in the 1983 General Election and setting the stage for years of weak electoral results compounded by limited access to resources due to the SNP’s financial reliance on members and branches and an absence of organizational support (Lynch 2013, pp. 175, 199).

Success from failure: the SNP since the 1990s

Unexpectedly the failure of the SNP trade union strategy would contribute to the party’s later successes by facilitating its transition to the new environment that emerged in Scotland at the end of the twentieth-century. In the decades that followed the SNP’s 1979 defeat, social mobility in Scotland increased significantly, contributing to a shrinking of the working class and an ideological convergence of the main parties (see Lynch 2009, p. 632). Under such conditions, the absence of strong societal linkages facilitated the party’s selection of leaders with wide popular appeal, such as Alex Salmond, who could reorient the party’s platform and policies. Despite Salmond’s membership in the avowedly left-wing 79 Group, his adherence to socialist beliefs, as Mitchell writes, “was never very convincing” (2016, p. 327) and his personal appeals become a core component of SNP electoral campaigns. Under Salmond and his temporary successor John Swinney,the party’s placement on the political spectrum could shift in response to changes in political and institutional conditions without its leaders needing to meet the frequently hard preferences of linked organizations, allowing the party more readily to adopt programmes in response to particular electoral circumstances. As long as the Tories governed in London, it advantaged the SNP to be positioned on the left in opposition, but with 1997 victory of a centrist New Labour Party and the opening of the Scottish Parliament 2 years later, the party moved to the centre, developing a flexible orientation that combined social democracy, civic nationalism, economic pragmatism, and even elements of populism (Lynch 2009, p. 631; Bennie 2016, p. 27). In many ways, the approach of the SNP leadership to professionalizing the party during this period mirrored the one taken by New Labour under Tony Blair (see Hassan 2009, p. 3); crucially, however, the SNP lacked the ties to Scotland’s trade unions that the Labour Party in Scotland held, making its efforts at internal reform and policy moderation less contentious than Scottish Labour’s during the same period.

Crucially, these changes were accompanied by an increasing disengagement of Scots from the organizational life of Scottish society. As Gallagher writes “since [the 1970s], the trend in Scotland has been for a strong community life to atrophy and people to become detached from institutions that may previously have been important reference points, such as a religious body, a trade-union or professional group, or a local form of identity” (2009, p. 538). Such developments likewise offered electoral benefits to an unlinked party such as the SNP since it could more easily establish the weaker and more contingent forms of linkage described by van Biezen and Poguntke (2014) to a wide array of groups. With looser ties to Scottish organizations, the SNP could maintain contradictions in its policies and programmes that would be more difficult for organizationally linked parties, which in turn would help it become, as one Scottish trade union official put it, “all things to all people” (interview, 2022).

Evidence for these contradictions can be seen in the development of the SNP’s relationships with both Scottish trade unions and businesses since devolution. The SNP’s outreach to unions increased as Scottish Labour’s links weakened during the Blair/Brown governments and contacts with the STUC grew after 2007, including twice-annual meetings between the First Minister and the Congress’s General Secretary. But such interactions fall far short of the efforts to penetrate the trade union movement that the party had attempted in the 1970s; as a current SNP official and trade unionist described it, the relationship today is characterized by a much more modest sharing of “best practices.” (interview, 2022). While some in Scottish Labour have sought to minimize the SNP’s efforts at trade union outreach—for example, in 2019 then-Labour MSP Neil Findlay called the SNP Trade Union Group, “a cynical flag of convenience to try to win trade unionists to the independence cause” that has “nothing to do with organizing nationalists to support industrial campaigns and struggles” (2019)—the view exists among union representatives that SNP MP and MSP trade union group members are more highly engaged on issues of importance to organized labour since they, unlike their Labour party counterparts, “have to seek it out” (interview with trade union official, 2022). And while SNP leaders in the 1970s viewed close ties to the trade unions to be essential for the party’s electoral chances, the period since 1999 has demonstrated that it is capable of significant electoral success with trade union voters even without such deep organizational links. In the 2011 Scottish Parliamentary elections which saw the SNP obtain an absolute majority, the party gained 14% more than Labour of the self-identified working class vote and a greater vote share among trade unionists than any other party (see McTavish 2016, p. 64).

Significantly the attempts of the SNP to cultivate its connections with organized labour have not come at the expense of the party’s relationship with Scottish business. The SNP began to seek business support early in the devolution period, reaching out to leadership in key Scottish industries, most notably in the financial sector, and promoting pro-business policies as part of an economic programme described by Cuthbert and Cuthbert (2009, p. 109) as “neoliberalism with a heart.” The party helped establish a foundation called “Business for Scotland” consisting of Scottish business officials who supported independence and developed close connections to the Scottish banking establishment (Camp 2014, p. 26; Gallagher 2009, p. 543). While First Minister Salmond could speak of creating a “Scottish Celtic Lion” modelled on the “Irish Celtic Tiger” strategy of enticing foreign investment by lowering corporate taxes and minimizing regulation after the 2007 election (Salmond 2008), the party could also quickly turn on Ireland as an exemplar after the global financial crisis in 2008, with SNP Minister for Enterprise Jim Mather labelling it “incompetent” (“SNP minister” 2010) and the party dropping references to the Scottish version of the Irish model (Green 2011). Such a reversal would have been far more problematic had the SNP established firm organizational ties with business groups, but absent such a relationship, the party would face no electoral backlash, improving significantly on its 2007 performance in the 2011 Scottish elections.

The focus of SNP members on the constitutional issue has also enhanced the party’s ability to carry out programmatic and organizational adjustments with limited membership interference despite massive membership growth. As a party objective, self-government has never been questioned by the SNP leadership (although tactical disagreements exist) or party members, whatever their socio-economic position or perspectives on other policy issues. A 2009 survey by Mitchell et al., found that over 70% of SNP members agreed or strongly agreed with the view that the primary goal of the party should be independence, with “all else” secondary (75). While the five-fold increase in new members after the 2014 referendum may have turned the SNP into “the kind of mass-membership party not seen in the UK for decades” (Bennie et al. 2021, p. 1188), it is unlikely to affect the autonomy of the party leadership. As Bennie, note, the new SNP members have not been particularly active in the party and few have sought to maintain the level of engagement witnessed during the referendum campaign. (2021, p. 1195). In this way, the SNP has managed to have the best of both words: the membership of a mass party with the flexibility and broad appeal of the catch all model.

The SNP has also benefitted from the inclusive interest group structure in the Scottish Parliament, particularly since 2007, which has structured and formalized interactions between organized interests and the Scottish executive and legislature. Designed to be more consensual than Westminster, the Scottish Parliament provides for a range of well-established channels for interest intermediation (interview with Scottish trade union official, 2022). Among these is a requirement of pre-legislative consultation for bills proposed by the Scottish Government that has led to regular interaction between government officials and affected parties, including voluntary groups, unions, professional bodies, private sector actors, and local and health authorities (Cairney et al. 2016, p. 333). Such structured access to the institutions of policymaking marks a significant change from the pre-devolutionary period, when interest groups relied on connections in political parties or more informal networks to link to political power (interview with MSP, 2022). One parliamentary affairs official from a leading Scottish religious organization estimated that 80% of all his engagement with Scottish government was carried out via formal channels (interview, 2022).


The unique position in which the Scottish National Party has found itself during its run of electoral dominance can be viewed as an unintended consequence of the party’s unsuccessful strategy of establishing links to the organizations of Scottish society in the 1970s. The concept of unintended consequences arose in social science to help explain how complexity may make it difficult for actors to interpret conditions accurately, predict the responses of others, and anticipate the implications of their actions (Pierson 2011, pp. 115–116). Uncovering the unintended effects of strategic action is a defining characteristic of historical institutionalism, a research approach that considers how temporal factors shape the origin, continuity, and patterns of change of social institutions (Hall and Taylor 1996; Hay and Wincott 1998, Fioretos et al. 2016). While historical institutionalists have invoked this concept largely to highlight disconnects between the goals of institutional designers and the effects of the institutions they create, the concept has similarly been used in the context of political parties and their strategies (see Walter and van der Eijk 2019). The leaders of the SNP who sought to fashion the party in accordance with the period’s dominant mass party model in the 1970s correctly interpreted the politics of the day, but misread future trends. Had the SNP effectively managed to penetrate the Scottish trade union movement and obtain the type of organizational support that had so benefited its Labour Party rivals, it may have found itself receiving a short-term electoral boost, but facing a more challenging path to enduring success in the politically de-aligned and organizationally de-linked Scotland of the twenty-first century. The party instead entered the 2000s with both an internal flexibility that allowed it to reorient its ideology and make organizational changes, and an external one, which facilitated its outreach to wide spectrum of voters.

The position of the SNP as a party with few durable links to the organizations of Scottish society is not without its downsides. In the 2020s, the party may be open to vulnerabilities on at least two fronts. The first concerns its electoral reliance on performance. As discussed above, the SNP has managed to maintain the support of Scottish voters largely because of its perceived performance since the 2007 Holyrood election first brought it into government. Yet maintaining the perception of stable and effective governance may depend on factors outside the party’s control, as the recent experience with COVID-19 demonstrates. To some extent this concern is mitigated for the SNP by its recent consolidation of independence supporting voters, who may—similar to the collateral groups from organized labour and religion during the era of the mass party—remain loyal the party even if its perceived governing effectiveness diminishes because of an overriding prioritizing of Scottish self-government. Yet this raises the second concern. The party may find that commitment to independence is not as enduring or powerful an identifier as class or confession.