West Prussia (region)

It was the eastern part of Marienwerder Region which voted to be incorporated within the Weimar Republic and joined the Province of East Prussia from 1922 to 1939.

As a result of the Treaty of Versailles following World War I, most of West Prussia, including much of the Marienwerder Region, was allocated to the Second Polish Republic.

The districts of Deutsch-Krone, Flatow, and Schlochau became part of the new Prussian Frontier March of Posen-West Prussia.

The districts of Graudenz, Konitz, Culm, Löbau, Schwetz, Strasburg in West Prussia, and Thorn became part of the Pomeranian Voivodeship of Poland.

At the Potsdam Conference, the three Allies assigned the region to Polish administration in August 1945, and the German-Polish Border Treaty confirmed the annexation in 1990.