The Red Army enters eastern Poland

Order 00485 initiated mass arrests targeting people accused of Polish espionage. The operation was part of the Great Terror’s national operations, which punished people collectively on the basis of...

Nikolai Bukharin and other defendants were convicted after a public trial marked by coerced confessions and sweeping conspiracy claims. The purges devastated the party, state institutions, military...

A joint decree ended the main mass operations and condemned “excesses,” while leaving the repressive system intact. Stalin’s government blamed abuses on subordinates even though the campaigns had been...

Stalin’s report at the congress celebrated the Soviet Union’s industrial and military development while presenting international rivalry as a long-term threat. The gathering followed the peak of the...

The public non-aggression treaty included secret protocols dividing spheres of influence in Eastern Europe. It gave both governments room to pursue expansion and exposed smaller states to decisions...

Soviet forces crossed the Finnish border after failed negotiations over security near Leningrad. The war exposed the costs of Stalin’s coercive diplomacy and the Red Army’s weaknesses after the...

The Soviet Politburo approved a proposal to execute thousands of Polish officers and prisoners held by the NKVD. The killings at Katyn and other sites were part of a broader effort to eliminate Polish...

The treaty ended the Winter War and transferred Finnish territory, including the Karelian Isthmus, to the Soviet Union. Soviet security demands gained territory but at high military and diplomatic...

Moscow demanded a new government and the entry of additional Soviet troops into Lithuania. Soviet pressure was followed by occupation and annexation, extinguishing Lithuanian independence. The episode...

Elections held under occupation offered voters a single approved list and were followed by petitions for incorporation into the Soviet Union. These procedures supplied a veneer of popular consent...