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National Museum of Nuclear Science & History

Steve Nelson

Chairman of the San Francisco Communist PartyUniversity of California, Berkeley

Soviet Atomic Bomb ProgramSpy

Steve Nelson was an American agent of the Communist Party.

Nelson joined the party in 1925 when he was living in western Pennsylvania. When he moved to the bay area in 1942 he became chairman of the San Francisco branch of the Communist Party. 

Almost immediately after taking that position, he became very involved in trying to uncover the work being done on the atomic bomb project at the University of California, Berkeley.  He befriended many of the physicists working on the project with Communist leanings. In March of 1943 he met with one of them, Joseph Weinberg, who gave him information regarding the bomb. Nelson would eventually pass this information on to agents of the Soviet government. 

Steve Nelson's Timeline
1903 Jan 1st Born in Subocka, Croatia.
1925 Joined the Communist Party.
1942 Became Chairman of the San Francisco branch of the Communist Party.
1943 Mar Obtained atomic bomb information from Joe Weinberg.
1950 Arrested under the Pennsylvania Sedition Act.
1993 Dec 11th Died in Cape Cod, MA.

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