The government region was created on 1 November 1905 as the third East Prussian
Regierungsbezirk out of the southern
districts of the two original administrative regions
Gumbinnen and
Königsberg, which had been established in 1815. It comprised the south of the former
Duchy of Prussia; the lands of the
Allenstein and
Rößel districts had belonged to the
Prince-Bishopric of Warmia, annexed by Prussia in 1772. In the
1920 East Prussian plebiscite all the Allenstein Region plus the was part of the Allenstein Plebiscite precinct, with the electorate voting for remaining with Germany by more than 97%. In 1945 following
World War II, Regierungsbezirk Allenstein was dissolved when East Prussia was partitioned between the
Republic of Poland and the
Soviet Union (Kaliningrad Oblast) and the Memel Territory was incorporated into the Sovjet Republic of Lithuania according to the resolutions at the
Potsdam Conference. == Demographics ==