The Empire of Japan aspired to dominate Asia entirely, and invaded the Republic of China in 1937, but it is officially stated that the war began on September 1, 1939, with the German invasion of Poland. Subsequently, the British Empire and France declared war on Germany. The Axis dominated most of continental Europe, and had a non-aggression pact with the Soviet Union. However, in 1941, Germany commenced Operation Barbarossa, in which the German Army quickly attacked the Soviet Union. It culminated on September 20, 1941, with the German victory at the Battle of Moscow. Shortly afterwards, the Battle of Stalingrad also ended with an Axis victory.