duty with his tank brigade was the attack on Finland during the Winter War of 1939-40. The effective military of this smaller nation surprised the aggressors with unyielding resolve, but Krivoshein fought with distinction and his promotion was quick. In less than two years he rose from commander of a motorized rifle division and then a tank division to commander of tank forces for a key Baltic Special Military District. With the Red Army's introduction of the traditional Russian ranks for its highest commanding staff, he became, in 1940, a major-general. Krivoshein received command of the 25th Mechanized Corps in April 1941. Reform of Soviet armored forces, 1941-1943 After the German invasion of the Soviet Union on June 22, 1941, Krivoshein's 25th Mechanized Corps constantly re-deployed and took part in an unsuccessful counterattack in the Bykhov area. In 1941–1943 Krivoshein was a head of Department of Training in the Main Directorate of the Red Army Tank Forces. The training of the Soviet tank crews had to respond to constantly changing demands to the crews such as introduction of the new tanks and search for the best size of tank formation in combat. Battle of Kursk In 1943 when the Red Army was preparing for the decisive Battle of Kursk, Krivoshein received command of the 3rd Mechanized Corps in Mikhail Katukov's 1st Tank Army of the Voronezh Front, commanded by Nikolai Vatutin. He and Katukov were the best defense tacticians in the Red Army armour. The Soviet high command assigned to Krivoshein a crucial task to fight in the first echelon in the south of the Kursk salient against German Army Group South and the most capable of all German Field Marshals----Erich von Manstein. Krivoshein took position in town of Oboyan, and together with 6th Tank Corps in Prokhorovka during the battle he faced the main weight of German assault, led by the top Wehrmacht panzer General Hermann Hoth. Krivoshein's forces were in dire technical disadvantage to German panzers. Against his corps, the Germans deployed their powerful Tiger I tanks, armed with 88mm guns that ranged approximately two kilometers. The Soviet tank T-34 had a smaller 76.2 mm gun with a shorter range of fire. On the first day of battle, on 1943 July 6, the Germans used Tigers together with enormous Ferdinand assault guns in an attack on Krivoshein. After fierce, tenacious fighting, by the end of the day German