In the autumn of 1939, Poland was invaded and divided in half by the Third Reich and the Soviet Union. Nazi Germany took over western Poland, while the U.S.S.R. took over the southeast. The Soviet invasion of eastern Poland on September 17, 1939, pursuant to provisions of the secret protocol of the Ribbentrop-Molotov Pact, came as a complete surprise to Poland's thirteen million residents and to diplomats around the world. In the months that followed, the Soviets imposed a complex administrative system in the region, with the goal of “Sovietizing” conquered territories. The dismantling of local religious institutions and the creation of Soviet schooling for millions of Polish, Ukrainian, Jewish, and Belorussian children were all part of this program. Additionally, starting in February 1940, the Soviet authorities carried out four punitive waves of deportation of some 320,000 Polish citizens (men, women, and children) into the interior of the U.S.S.R.