Posen-West Prussia
The Frontier March of Posen-West Prussia (, ) was a province of Prussia from 1922 to 1938. Posen-West Prussia was established in 1922 as a province of the Free State of Prussia within Weimar Germany, formed from merging three remaining non-contiguous territories of Posen and West Prussia, which had lost the majority of their territory to the Second Polish Republic and Free City of Danzig in the Treaty of Versailles. From 1934, Posen-West Prussia was "de facto" ruled by Brandenburg until it was dissolved by Nazi Germany, effective 1 October 1938 and its territory divided between the Prussian provinces of Pomerania, Brandenburg and Silesia. Schneidemühl (present-day Piła) was the provincial capital. Today, the province is entirely contained within the modern state of Poland.