Molotov-Ribbentrop pact

A non-aggression pact negotiated by Germany and the Soviet Union on August 23, 1939 and often referred to as the Molotov-Ribbentrop pact after its chief negotiators. In a secret addendum to this agreement, eastern Europe was divided between the Nazi and Soviet powers. In September 1939, Germany and the U.S.S.R. invaded and partitioned Poland.