The region that was Prussia is made up mainly of low-lying land, drained by several rivers, notably the Rhine; the Weser; the Oder; and the Elbe, which divided the state into roughly equal eastern and western parts. After Berlin, the largest cities of the area were Cologne, Breslau (Wrocław), Essen, Frankfurt, Düsseldorf, Hanover, Dortmund, Magdeburg, and Königsberg (Kaliningrad). The region also included the gigantic industrial Ruhr district.
Industrially and politically the most prominent state of Germany prior to World War II, Prussia was partitioned among the four Allied occupation zones after 1945. In 1947 the Allied Control Council for Germany formally abolished the state of Prussia. This action not only confirmed an accomplished fact; it was also intended as a blow against the spirit of German militarism and aggression, long held to be connected with Prussia. Most of the former Prussian provinces became part of the new states of the Federal Republic of Germany and of the German Democratic Republic (now reunified). The USSR annexed the northern part of East Prussia; Poland acquired the rest of East Prussia, as well as all Prussian territory E of the Oder and Neisse rivers.