What impact did the new blitzkrieg strategy have on the war?

Despite the continuing war with Great Britain, German forces invaded the Soviet Union in June 1941. At first, the German Blitzkrieg seemed to succeed. Soviet forces were driven back more than 600 miles to the gates of Moscow, with staggering losses. In December 1941, Hitler unilaterally declared war on the United States, which consequently added its tremendous economic and military power to the coalition arrayed against him. A second German offensive against the Soviet Union in 1942 brought German forces in the east to the shores of the Volga River and the city of Stalingrad. However, the Soviet Union launched a counteroffensive in November 1942, trapping and destroying an entire German army at Stalingrad.

Germany proved unable to defeat the Soviet Union, which together with Great Britain and the United States seized the initiative from Germany. Germany became embroiled in a long war, leading ultimately to its defeat in May 1945.