
Calhoun County was named for Vice President John C. Calhoun, the seventh Vice President of the United States. It was created from parts of Early and Baker counties on February 20, 1854.
Rival political factions disagreed about whether the county seat should be in Concord, a community north of present-day Leary, or in Dickey, then known as Whitney. As a compromise, a spot halfway between Concord and Whitney was chosen for the county seat, and the town of Morgan was established there.
In 1923 the state legislature moved the county seat to Arlington as directed by a county referendum. This decision was reversed in 1929, restoring Morgan as the county seat.