Lavrenty Beria
After Vladimir Lenin died in 1924 at age 53 Joseph Stalin replaced Lenin after his death and Lavrenty Beria joined the NKVD led by Genrikh Yagoda (1891-1938) from 1934-1936 and Nikolai Yezhov from 1936-1938 which both replaced Felix Dzerzhinsky (1877-1926) and Vyacheslav Menzhinsky (1874-1934) in 1926 and in 1934. On 1 December 1934 the NKVD killed Sergei Kirov and it led to the Great Purge in 1936-1938. But in 1939 during the start of World War 2 the NKVD was involved in the Invasion of Poland (1939).