League of Nations
Resolving the border demarcation crisis between Poland and Lithuania
Vilnius, Lithuania
Poland and Lithuania both regained their independence but soon became immersed in territorial disputes. During the Polish–Soviet War, Lithuania signed the Moscow Peace Treaty with the Soviet Union that laid out Lithuania's frontiers. On 7 October 1920, the League negotiated the Suwałki Agreement establishing a cease-fire and a demarcation line between the two nations.