Buell's victory at Perryville was unconvincing and his pursuit of CSA Gens. Bragg & Smith halfhearted.
Both Union and Confederate generals' reputations will be tarnished by the battle -- the Union army will be reorganized and Buell eventually forced to resign; CSA Gen. Bragg will have to answer to Jefferson Davis and then keep his job for another year before being relieved of command, after Chattanooga.
Some historians consider Antietam and Perryville as markers of the war's great turning point.
Shelby Foote thought enough of Perryville to make it the finale of volume 1 of his narrative. Bruce Catton thought the same of Antietam, but barely noticed Perryville.