The Southwestern Front was on the main axis of attack by the German Army Group South during Operation Barbarossa. At the outbreak of war with Germany, the Front was commanded by Mikhail Kirponos and contained the Soviet 5th, 6th, 26th, and 12th Armies along the frontier. 16th and 19th Armies were in reserve behind the forward forces. These forces took part in the tank battles in western Ukraine and were surrounded and destroyed at the Battle of Uman and the Battle of Kiev (1941) in August and September 1941. Kirponos himself was killed during the Battle of Kiev.