Ever Ready to Go: The Multiple Exiles of Leo Szilard


I argue that to understand the life and work of Leo Szilard (1898–1964) we have to understand, first, that he was driven by events to numerous departures, escapes, and exiles, changing his religion, his language, his country of residence, and his scientific disciplines; second, that he was a man haunted by major moral dilemmas throughout his life, burdened by a sincere and grave sense of responsibility for the fate of the world; and third, that he experienced a terrible sense of déjà vu: his excessive sensitivity and constant alertness were products of his experiences as a young student in Budapest in 1919. The mature Szilard in Berlin of 1933, and forever after, was always ready to move. I proceed as follows:After a brief introduction to his family background, youth, and education in Budapest, I discuss the impact of his army service in the Great War and of the tumultous events in Hungary in 1918–1919 on his life and psyche, forcing him to leave Budapest for Berlin in late 1919. He completed his doctoral degree under Max von Laue (1879–1960) at the University of Berlin in 1922 and his Habilitationsschrift in 1925. During the 1920s and early 1930s, he filed a number of patents, several of them jointly with Albert Einstein (1879–1955). He left Berlin in March 1933 for London where he played a leading role in the rescue operations for refugee scientists and scholars from Nazi Germany. He also carried out notable research in nuclear physics in London and Oxford before immigrating to the United States at the end of 1938. He drafted Einstein’s famous letter of August 2, 1939, to President Franklin D. Roosevelt, worked in the Manhattan Project during World War II, initiated a petition to President Harry S. Truman not to use the bomb on Japan, and immediately after the war was a leader in the scientists’ movement that resulted in civilian control of nuclear energy. In 1946 he turned to biology, in which his most significant contribution was to formulate a theory of aging. In 1956 von Laue led an effort to invite him to head a new institute for nuclear physics in West Berlin, which he ultimately declined at the end of 1959. He remained in the United States, becoming a highly visible public figure, speaking, writing, and traveling extensively, and even corresponding with Soviet Premier Nikita S.Khrushchev and President John F. Kennedy to promote the international control of nuclear weapons. In retrospect, although Szilard was a man of many missions, his life story could be read as that of a man of conscience with but a single mission, to save mankind.

This is a preview of subscription content, access via your institution.

Author information



Corresponding author

Correspondence to Tibor Frank.

Additional information

Tibor Frank is Professor of History at Eötvös Loránd University in Budapest, Hungary. His paper originated in 1988–1990 when he carried out substantial archival research as a Fulbright Visiting Professor at the University of California, Santa Barbara, and at the University of California at Los Angeles, and is based largely on the Leo Szilard Papers in the Mandeville Special Collections Library of the Geisel Library at the University of California, San Diego, in La Jolla. He completed his archival research during 2003–2004 as a Humboldt Research Award Winner at the Max Planck Institute for the History of Science in Berlin.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Frank, T. Ever Ready to Go: The Multiple Exiles of Leo Szilard. Phys. perspect. 7, 204–252 (2005). https://doi.org/10.1007/s00016-004-0236-9

Download citation

Key words.

  • Leo Szilard
  • William Beveridge
  • Arthur H. Compton
  • Lord Cherwell
  • Albert Einstein
  • Enrico Fermi
  • Leslie R. Groves
  • John F. Kennedy
  • Max von Laue
  • John von Neumann
  • Friedrich A. Paneth
  • Max Planck
  • Michael Polanyi
  • Erwin Schrödinger
  • Edward Teller
  • Harold C. Urey
  • Eugene Wigner
  • Budapest
  • Hungary
  • Berlin
  • Great War
  • Nazi Germany
  • Szilard-Chalmers reaction
  • World War II
  • Manhattan Project
  • Metallurgical Laboratory
  • Franck Report
  • Atomic Bomb
  • Cold War
  • Atomic Stalemate
  • patents
  • psychology
  • émigré scientists
  • nuclear physics
  • nuclear fission
  • nuclear-chain reaction
  • scientists’ movement
  • biophysics
  • theory of aging