 Complete the following phrase:  The Western powers remained unaware of the top secret Nazi-Soviet Pact in 1939, which paved the way for World War II. The German surrender in May 1945 was followed by a massive change in the political geography of Europe. Polands borders were redrawn by the Allies according to the demands made by Josef Stalin during the Tehran Conference, confirmed as not negotiable at the Yalta Conference of 1945. The Polish government-in-exile was excluded from the negotiations. The territory of Poland was reduced by approximately 20 percent. Before the end of 1946 some 1.8 million Polish citizens were 