This treaty granted the Soviet Union military bases inside Lithuania, directly enabling the subsequent Soviet occupation of the country in 1940.
Key Facts
- Date signed
- October 10, 1939
- Soviet troops allowed
- 20,000 troops
- Soviet military bases established
- 5 bases
- Territory transferred to Lithuania
- Approximately one fifth of the Vilnius Region
- Capital returned to Lithuania
- Vilnius
By the Numbers
Location
Cause → Event → Consequence
Following the Soviet invasion of eastern Poland in September 1939, the USSR gained control of the Vilnius Region. Seeking to extend its strategic influence over the Baltic states, the Soviet Union pressured Lithuania, Estonia, and Latvia into accepting mutual assistance treaties that would permit Soviet military installations on their soil.
On October 10, 1939, the Soviet Union and Lithuania signed a bilateral mutual assistance treaty. Lithuania received approximately one fifth of the Vilnius Region, including its historical capital Vilnius, in exchange for permitting the Soviet Union to establish five military bases housing up to 20,000 troops across Lithuanian territory.
Despite official assurances that Lithuanian sovereignty would remain intact, the treaty effectively subordinated Lithuania to Soviet strategic control. It was characterized by The New York Times as a 'virtual sacrifice of independence' and paved the way for the first Soviet occupation of Lithuania in June 1940, ending the country's independent statehood.
Political Outcome
Lithuania received the Vilnius Region but was compelled to host five Soviet military bases with 20,000 troops, undermining its sovereignty and leading to full Soviet occupation in 1940.
Lithuania was an independent state without Soviet military presence on its soil.
The Soviet Union gained permanent military bases inside Lithuania, effectively dominating the country's security and foreign policy.