Ambrose Burnside (1824–1881) is one of the most likable of all Civil War generals. Modest, friendly to all, and interested in the well-being of his men, Burnside was an ideal division commander, perhaps even corps commander, but he did not have the kind of killer instinct necessary to be commander of an entire army (the same could be said for McClellan). Lincoln had previously offered high command to Burnside, who had turned it down. On this occasion, he accepted, becoming the new commander of the Army of the Potomac.

Burnside at once began to reorganize the army. There were so many corps and divisions that the command chain had become unwieldy. He, therefore, divided it into three grand corps. Whatever other faults he might commit, Burnside would not demonstrate the “slows” as had McClellan.