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British intelligence officer Kim Philby was also a Soviet double agent. He was part of the spy group known as the Cambridge Five and leaked classified information to the Soviet Union during World War II and the Cold War. He later defected to Moscow and spent his final years there.
Richard Sorge was a German journalist and Soviet military intelligence officer. He was active before and during the Second World War. He worked undercover in both Nazi Germany and the Empire of Japan under the codename, "Ramsay." He was arrested, tortured, and hanged in 1944. In 1964, he was posthumously awarded the title of Hero of the Soviet Union.
American chemical engineer George Koval was one of the most significant Soviet spies of the 20th century. Born to Belarusian immigrants in Iowa, Koval later moved to Russia with his family. Codenamed Delmar, he later worked in the U.S. atomic laboratories and supplied classified information to Russia.
Manfred Ramminger was a German architect and KGB agent. He is best remembered for stealing an American AIM-9 Sidewinder, which he brought to the Soviet Union. In 1968, Manfred Ramminger was arrested along with his aides by West German authorities.
