Armored spearheads thrust deep into Soviet territory, driving toward Leningrad, Moscow, and the Ukraine and cutting off entire Soviet armies. Despite tremendous losses, Russian military forces withdrew farther into the country and continued to resist. Nazi expectations of a quick victory evaporated, and the onset of winter caught the Germans unprepared. Thirty miles short of Moscow their advance ground to a halt, and the Soviets launched massive counterattacks.
— A Brief History of the U.S. Army in World War II
by Center of Military History