Rudy Baker, a Communist Party United States of America official, is today best known for his role as head of the CPUSA"s underground secret apparatus.
Baker was born in 1898 in Vukovar, Kingdom of Hungary, probably under the name Rudolph Blum.
He succeeded to the position in 1938, after the removal of J. Peters. Baker had little formal education, and emigrated to the United States with his family in 1909. He joined the Communist Party of the United States at its founding, in 1919.
He went to Moscow and trained at the International Lenin School from 1927 to 1930.
Baker shows up in the Venona project decryptions of Soviet codes under the cover name SON. He may also be RUDI. In these messages, SON is the head of the party"s covert arm or secret apparatus, which Baker took over in mid-1938 after the defection of Whittaker Chambers.
Notably, all of the Communist International messages to SON were sent after Baker visited Moscow in January 1939 to brief Communist International officials on the status of the party"s secret apparatus (after Baker took over its operations). In May 1942, General Pavel Fitin, the head of Komitet Gosudarstvennoy Bezopasnosti (Committee for State Security) foreign intelligence directorate states in a message to Dimitrov found in the Communist International Archives, "We are forwarding a telegram we received from New York addressed to you from Rudy". This telegram is signed SON.
He became a member of the Communist Party of the Soviet Union during that period.