Most military historians have difficulty comprehending the miracle that took place in late 1941 and early 1942 in the Soviet Union. In the summer of 1941, the German Army routed the Red Army as it had routed the Polish, British, French and other armies in 1939, 1940, and early 1941. When Hitler invaded the Soviet Union in June, 1941 and his legions quickly overcame the Soviet divisions they met, it appeared that Hitler would succeed as he had before. A major portion of the pre-war Red Army had been completely annihilated, millions of prisoners taken, and the most populous and developed provinces of the Soviet Union were occupied by the Germans and their allies. How was it possible for the Red Army to recover from these seemingly disastrous defeats to stop the German advance at the gates of Moscow? The author's detailed examination shows that, far from carelessly throwing thousands of disorganised untrained men into battle, the Soviets wisely used the resources at hand to resist and drive back the invaders once the initial shock had been absorbed. Dunn reveals how the Soviets systematically trained men as replacements for casualities in existing units - often renaming the unit, a move which confused German intelligence and one which continues to confound historians today.