Short answers, pulled from the story.
The Smolensk operation, codenamed Suvorov, was a Soviet strategic offensive conducted from the 7th of August to the 2nd of October 1943. Led by General Andrei Yeremenko on the Kalinin Front and General Vasily Sokolovsky on the Western Front, it aimed to expel German forces from the Smolensk and Bryansk regions after more than two years of occupation.
General Andrei Yeremenko commanded the Kalinin Front and General Vasily Sokolovsky commanded the Western Front during the Smolensk operation. Together their forces executed the campaign in three stages between August and October 1943.
Smolensk was liberated by Soviet forces on the 25th of September 1943, following an assault crossing of the northern Dnieper and a full night of street fighting. Roslavl was recaptured the same day.
As many as 55 German divisions were committed to countering the Smolensk operation. These were divisions unavailable to reinforce German defenses along the Dnieper in the south, where Soviet forces simultaneously conducted the Lower Dnieper Offensive.
German defensive lines during the Smolensk operation extended 100 to 130 kilometers in depth and included five or six separate lines. The forward defense zone alone contained a main line 5 kilometers deep, with firing points at a density of six or seven per kilometer and, in some areas, solid antitank moats reinforced with artillery and machine gun positions.
When Soviet troops entered the liberated territories, they found that almost 80% of urban living space in Smolensk Oblast had been destroyed, along with 50% of rural housing and most of the region's industry and agriculture. Soviet forces also discovered evidence of war crimes carried out by SS Einsatzgruppen units during the period of German occupation.