did germany succesfully invade poland
For the Soviet invasion of Poland in 1920, see PolishâSoviet War. The Soviet invasion of Poland was a Soviet military operation that started without a formal declaration of war on 17 September 1939. On that day, sixteen days after Nazi Germany invaded Poland from the west, the Soviet Union did so from the east.The invasion ended on 6 October 1939 with the two-way division and annexation of the entire Second Polish Republic by Germany and the Soviet Union.In early 1939, the Soviet Union entered into strategic alliance negotiations with the United Kingdom, France, Poland, and Romania against Nazi Germany.n early 1939, the Soviet Union entered into strategic alliance negotiations with the United Kingdom, France, Poland, and Romania against Nazi Germany.