The German armed forces experienced their first major defeat with the lost aerial war against Great Britain in the summer of 1940. The offensives of the «Axis Powers» Italy and Germany against British troops in North Africa, on the Balkan Peninsula and in Greece were successful, but the benefits resulting from them were not used to further weaken Great Britain's position in the Mediterranean region. Instead the German armed forces invaded the USSR on 22 June 1941.
Hitler regarded the «Russian campaign» not only as a war of conquest through which the great industrial centres, the fruitful regions in southern Russia and the oil fields in the Caucasus would come into German hands. In his «world-outlook war» against Russia, Hitler above all planned the destruction of «Jewish-Bolshevist intelligence» as well. Disregarding all stipulations concerning human rights, a war of extermination against the Russian civilian population with unprecedented brutality, especially against the Jews, in which millions of people fell victim.
The planned quick subjection of Russia failed due to the power of resistance of the Red Army and due to the onset of winter for which the Wehrmacht was unprepared. Although military observers declared the war against the Soviet Union as lost already during the winter of 1941/42, however, and advised Hitler to make a peace agreement with Stalin, the fighting continued. With the declaration of war on the USA, whose naval base Pearl Harbour was attacked on 7 December 1941 by Germany's ally Japan, the war became a world war.
The National Socialist party functionaries and ministers decided on the systematic extermination of the Jews at the «Wannsee Conference» in January 1942. By the end of the war over six million Jews, but also millions of non-Jewish Poles, Russians, Sinti and Roma were murdered in the extermination camps by the end of the war.