Yan Karlovich Berzin

Yan (Ian) Karlovich Berzin (Russian: Ян Карлович Берзин; Latvian: Jānis Bērziņš; real name Pēteris Ķuzis; 25 November [O.S.

13 November 1889] 1889, Kreis Riga (now in Zaube parish), the Russian Empire – 29 July 1938, Moscow, the USSR), was a Latvian Soviet communist politician and military intelligence officer.

According to his former subordinate, Walter Krivitsky, Ķuzis led a guerrilla detachment in his native country of Latvia at the age of 16 during the 1905 Revolution, and was wounded, caught, and sentenced to death.

In September 1936, he was sent to Madrid, under the nom de guerre Grishin, as chief military adviser to the Republican side in the Spanish Civil War.

On 14 December 1948, Alexander Barmine, former chargé d'affaires at the Soviet embassy in Athens, Greece, advised Federal Bureau of Investigation agents that Berzin informed him prior to Barmine's 1937 defection that Owen Lattimore, the head of the U.S. Office of War Information in the Pacific during World War II, was a Soviet agent.