In March and April 1865, as the war near its close, McCook commanded the First Division in Wilson's Raid through Alabama and Georgia, as well as at the Battle of Selma, where the federal cavalry dealt a crushing defeat upon Nathan Bedford Forrest. In early May, McCook's division was assigned to re-establish federal control and authority in Florida, whose ardent secessionist governor, John Milton, had shot himself in the head rather than submit to Union occupation.