On September 17, when it was clear that the German invasion had succeeded, the Red Army entered the eastern part of Poland in accordance with the secret agreements between Germany and the USSR in the Ribbentrop-Molotov pact.
On October 26, 1939, the Germans divided the Polish areas that it had occupied into two sectors: One sector was annexed to Germany and became part of the Reich; the other was named the General Government and placed under a German civil administration headed by Hans Frank.
