The Second Battle of Smolensk was a major World War II Red Army offensive in western Russia, staged almost simultaneously with the Battle of the Lower Dnieper. The two-month offensive led by Generals Andrei Yeremenko and Vasily Sokolovsky was aimed at clearing the German presence from the Smolensk and Bryansk regions. Smolensk had been under German occupation since the first Battle of Smolensk in 1941. Despite an impressive German defense setup, the Red Army was able to stage several breakthroughs, liberating several major cities, including Smolensk and Roslavl, and moving into occupied Belorussia. Although playing a major military role in its own right, the Smolensk Operation was also important for its effect on the Battle of Dnieper. It has been estimated that as many as 55 German divisions were committed to counter the Smolensk Operation—divisions that were critically needed to prevent Soviet troops from crossing the Dnieper River in the south. Additionally, the operation allowed the Red Army to repulse German forces definitively from the Smolensk landbridge, historically the most important approach for an attack on Moscow from the west.