Leo Szilard (1898-1964), Hungarian-American physicist and discoverer of nuclear fission. Szilard was born in Budapest, and obtained his doctorate in engineering in Berlin in 1922. With Hitler's rise to power, Szilard moved to England and started research into nuclear physics. In 1934 he foresaw the idea of nuclear fission, the splitting of atoms by neutrons in a chain reaction. In 1937 he moved to America, and during the war collaborated with Fermi on the construction of the first atomic pile. After the war Szilard became increasingly horrified by nuclear weapons, becoming a leader of the movement for the peaceful use of atomic power.