The German-Soviet Pact was an agreement signed by Nazi Germany and the Soviet Union on August 23, 1939. It was negotiated by German Foreign Minister Joachim von Ribbentrop and Soviet Foreign Minister Vyacheslav Molotov. Commonly called the German-Soviet Pact or the Molotov-Ribbentrop Pact, it is also known as the Nazi-Soviet Pact or the Hitler-Stalin Pact. 

Two German sentries stand guard at Augustow on the demarcation line between Soviet- and German-occupied Poland.

The German-Soviet Pact consisted of two parts, one public and one secret. The public part was a non-aggression pact in which each signatory promised not to attack the other. They further promised that, should one of the two signatories be attacked by a third country, the other signatory would not provide assistance of any kind to the third country. In addition, they each agreed not to participate in any arrangement with other powers that was directly or indirectly aimed at the other. The non-aggression agreement was to last for ten years and be automatically renewed for an additional five years if neither signatory moved to end it.

The secret part of the pact was a protocol that established Soviet and German spheres of influence in eastern Europe. It recognized Estonia, Latvia, and Bessarabia as falling within the Soviet sphere. The signatories agreed to divide Poland along the line of the Narev, Vistula and San Rivers.

German and Soviet forces partition Poland

The German-Soviet Pact in Action

With the Molotov-Ribbentrop pact in effect, Germany attacked Poland on September 1, 1939, without fear of Soviet intervention. On September 3, 1939, Britain and France, having guaranteed to protect Poland's borders five months earlier, declared war on Germany. Just over two weeks later, on September 17, the Soviet Union invaded Poland from the east. These events mark the beginning of World War II

Germany and the Soviet Union then moved to take control of the spheres of influence delineated in the secret protocol of the non-aggression pact. They amended the protocol to assign Lithuania and the city of Vilnius (then Wilno, Poland) to the Soviet sphere and adjusted the boundary they had set in Poland. On September 29, 1939, they partitioned Poland between them. Germany occupied western and most of central Poland and proceeded to annex the western provinces to the Reich. The Soviet Union occupied and annexed the rest of Poland. 

Also according to the agreement, the Soviet Union annexed other territories in its sphere of influence. On November 30, 1939, the Soviets attacked Finland. After a four-month war, they annexed Finnish territory along the Soviet border, particularly the area near Leningrad (now St. Petersburg). In the summer of 1940, the Soviets occupied and incorporated the Baltic states of Estonia, Latvia, and Lithuania. They also seized the Romanian provinces of Northern Bukovina and Bessarabia.

Eastern Europe after the German-Soviet Pact, 1939-1940

The End of the German-Soviet Pact

Hitler regarded the German-Soviet non-aggression pact as a tactical and temporary maneuver. He never intended to uphold the terms of the agreement for ten years. His long-range plan had always been for German forces to attack the Soviet Union and establish Lebensraum (living space) for the Germans in the territories they seized. Before taking this step, however, Hitler intended to subdue Poland and defeat France and Great Britain. The non-aggression pact allowed Germany to fight these intermediate wars without fear of a Soviet attack, thereby avoiding a two front war. 

In July 1940, one month after Germany defeated France, Hitler ordered preparations for war against the Soviet Union. German diplomats worked to secure Germany's flank in southeast Europe. In November 1940, Hungary, Romania, and Slovakia joined the Axis alliance. During the spring of 1941, Hitler initiated his European allies into plans to invade the Soviet Union.

On December 18, 1940, Hitler signed Directive 21 (code-named “Operation Barbarossa”), the first operational order for the invasion of the Soviet Union. From the beginning of operational planning, German military and police authorities intended to wage a war of annihilation against what they saw as the Soviet Union’s “Judeo-Bolshevik” Communist government, as well as Soviet citizens, particularly the Jews.

On June 22, 1941, German forces invaded the Soviet Union, less than two years after signing the German-Soviet Pact.