The 5th Guards Tank Army was formed on 10 February 1942. Its organisation varied throughout its history, but in general included two or more Guards Tank Corps and one or more Guards Mechanized Corps. It was considered an elite formation. Under Red Army doctrine of deep operations, Tank Armies were primarily to be used for large-scale exploitation of major offensives. Once a breach in enemy lines had been made by other units (typically Shock Armies or combined-arms armies), the tank army would be inserted into the gap to drive deep into enemy territory, attacking rear areas and seizing major communications centers to disrupt the enemy reactions. Tank armies were expected to penetrate up to several hundred kilometers into the enemy rear.