Sikorski-Mayski Agreement

The Sikorski–Mayski Agreement was a treaty between the Soviet Union and Poland, signed in London on 30 July 1941. Its name is taken from its two most notable signatories: Polish Prime Minister Władysław Sikorski and Soviet Ambassador to the United Kingdom Ivan Mayski.

After signing the German-Soviet Nonaggression Treaty in 1939, the Soviet Union took part in the invasion of Poland and its subsequent dismemberment. The Soviet authorities declared Poland to be non-existent, and all former Polish citizens from the areas annexed by USSR were treated as if they were Soviet citizens. This resulted in the arrest and imprisonment of approximately 2 million Polish citizens (including a quarter of a million POWs and 1.5 million deportees) by the NKVD and other Soviet authorities.

When the international situation of the Soviet Union changed with the outbreak of the Soviet-German War in 1941, Stalin began to seek help from other countries opposing Germany. Strongly encouraged by British Foreign Office diplomat Anthony Eden, Sikorski, on 5 July 1941, opened negotiations with the Soviet ambassador to London, Ivan Mayski, to re-establish diplomatic relations between Poland and the Soviet Union. Sikorski was the architect of the agreement reached by the two governments, signed on 30 July 1941. A further military alliance was signed in Moscow on 14 August 1941. Later that year, Sikorski went to Moscow with a diplomatic mission (including the future Polish ambassador to Moscow, Stanisław Kot, and chief of the Polish Military Mission in the Soviet Union, General Zygmunt Szyszko-Bohusz).

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