On 22 June 1941 Germany attacked the Soviet Union and her Panzer divisions were to play a major role in this titanic struggle. Although overwhelmed by Soviet numbers, the superior skill and capability of the German Panzer divisions meant that in three months the Germans had advanced deep into Soviet territory. However, after these initial successes the German offensive began to falter, culminating in the disastrous defeat at Kursk. This book describes the organisational history of the Panzer divisions, from the early successes of 1941 through to the introduction of revised Blitzkrieg tactics as the war progressed.