Treaty of Tartu (Finland–Russia)

The Treaty of Tartu, signed on October 14, 1920, between Finland and Soviet Russia (represented by the Russian Socialist Federative Soviet Republic or RSFSR), marked the end of the Finnish-Soviet War (1918-1920), also known as the Heimosodat (Kinship Wars) or the Finnish Civil War and its associated border conflicts. It formally defined the border between Finland and Russia, which largely followed the old border of the Grand Duchy of Finland within the Russian Empire, with some adjustments.

Key provisions of the treaty included:

• Territorial concessions: Finland gained Petsamo (Pechenga), granting Finland access to the Arctic Ocean. Other smaller border adjustments also occurred in Finland's favor.
• Soviet guarantees for East Karelia: The treaty promised autonomy for East Karelia, a region inhabited by Finno-Ugric peoples, within Soviet Russia. This promise was not fulfilled.
• Finnish concessions: Finland ceded Repola and Porajärvi, which Finnish volunteer forces had occupied during the war, back to Soviet Russia.
• Demilitarization: Certain areas near the border were to be demilitarized.
• Economic relations: The treaty addressed issues of trade and property rights.

The Treaty of Tartu was of great significance for Finland, as it secured Finnish independence from Soviet Russia and defined its eastern border. However, the failure of the Soviet Union to grant autonomy to East Karelia became a source of tension between the two countries in the interwar period. The territorial adjustments defined by the treaty remained in effect until the Winter War in 1939, when the Soviet Union invaded Finland and seized some of the territory ceded to Finland under the treaty, including Petsamo. The Moscow Peace Treaty of 1940 formalized these territorial changes. Following the Continuation War (1941-1944), the 1940 borders were reaffirmed, and the Treaty of Tartu was effectively superseded.