China and the Soviet Union sign a treaty of alliance

The organization expelled Yugoslavia’s Communist Party after its leadership resisted Soviet control. The split showed that anti-fascist and socialist movements could face pressure to subordinate...

At the end of the VASKhNIL session, Trofim Lysenko’s doctrine was declared the official line, with Stalin’s support. Genetics was marginalized, research and teaching were disrupted, and scientists...

The Soviet Union and allied governments created Comecon to coordinate economic relations in the emerging Eastern Bloc. It offered a framework for trade and planning but also reinforced Moscow’s...

The successful test ended the U.S. monopoly on nuclear weapons and intensified the arms race. Soviet scientific work and industrial mobilization occurred in a state system marked by secrecy, forced...

The meeting opened negotiations over the relationship between the Soviet Union and the newly founded People’s Republic of China. Their talks revealed both revolutionary solidarity and bargaining...

North Korean forces invaded South Korea. Newly available Soviet records show Stalin approved Kim Il Sung’s plan after seeking assurances about Soviet and Chinese involvement. The war devastated Korean...

The congress met thirteen years after the previous one, reflecting the concentration of authority during wartime and postwar years. Stalin’s speech presented a global ideological struggle, while the...

The government accused mostly Jewish physicians of conspiring to murder Soviet leaders. The campaign intensified state antisemitism; Stalin’s death soon halted the case, and his successors later...

Stalin’s death ended nearly three decades of personal dictatorship. His rule left a transformed industrial and military power, alongside mass famine, executions, forced labor, deportations, and a...

The Presidium of the Supreme Soviet issued an amnesty that released many prisoners serving shorter sentences and reduced penalties for some offenses. It did not free most political prisoners, but it...