On 16 August 1945, in Moscow, Poland (Provisional Government of National Unity) and the Soviet Union sign the agreement on the Polish–Soviet state frontier — the document that formally fixes the Curzon Line, with deviations in Poland’s favour, after Yalta.

Signatories are Edward Osóbka-Morawski and Vyacheslav Molotov. The treaty confirms the cession of pre-war Kresy to the USSR and delimits the border from the Baltic Sea to the tripoint with Czechoslovakia in the Carpathians, including the former East Prussia segment.

Article 1 provides for 5–8 km deviations and additional concessions (Bug/Sołokija, part of Białowieża Forest). Entry into force followed the exchange of ratification instruments (5 February 1946).

The text was published in Dziennik Ustaw and registered in treaty collections.

For postwar Poland, 16 August 1945 marks the eastern border signature.

The document is available on Polish Wikisource (official Polish text).

The Polish–Soviet border agreement of 16 August 1945 remains the post-Yalta Curzon Line milestone.

Image: Poland; Wikimedia Commons. Cropped to 16:9.

Source consulted: Polish–Soviet border agreement of August 1945. Treaty text: Polish Wikisource — Border agreement 16 August 1945.