The territory lay to the east of the Molotov-Ribbentrop line and was consequently occupied by the Soviet Union and incorporated into the Belarussian Soviet Socialist Republic. In the aftermath of the German attack on the Soviet Union in June 1941, the western portion of Soviet Belarus (which, until 1939, belonged to the Polish state), was placed under the German Civilian Administration ("Zivilverwaltungsgebiet"). As Bezirk Bialystok, the area was under German rule from 1941 to 1944 without ever formally being incorporated into the German Reich.