Red Army troops enter the Baltic states

The agreement granted the USSR military bases in Latvia. Officially framed as mutual assistance, it constrained Latvian sovereignty and foreshadowed further Soviet pressure on the Baltic states.

The treaty transferred Vilnius to Lithuania but required Soviet military bases on Lithuanian territory. It combined a territorial concession with a powerful strategic foothold that compromised...

The Soviet government accused Finland of shelling Soviet positions and used the incident to intensify the crisis. Finland denied responsibility; the event became a pretext for terminating the...

Soviet forces crossed into Finland after negotiations over border security and territorial concessions failed. The invasion was an act of aggression that produced heavy civilian and military losses...

The League condemned the Soviet invasion of Finland and expelled the USSR. The decision exposed the weakness of collective security and the limits of Soviet claims to defend peace through...

Following a Soviet ultimatum, Romania withdrew and Soviet troops entered Bessarabia and Northern Bukovina. The move expanded Soviet control and affected Romanian, Ukrainian, Jewish, Russian, and other...

Newly installed assemblies adopted resolutions seeking incorporation. These votes followed Soviet military occupation and political coercion; the Soviet and Baltic accounts of the process remain...

The USSR created the Moldavian SSR from most of Bessarabia and the Moldavian Autonomous SSR, while northern Bukovina and parts of Bessarabia were attached to the Ukrainian SSR. The new borders divided...

The USSR formally incorporated Lithuania after its occupation and a controlled political process. Soviet institutions and land, economic, and security policies were imposed amid resistance,...

The USSR formally incorporated Latvia following occupation and a staged political process. The change brought Soviet nationalization, political arrests, and institutional restructuring, while...