Calhoun County was created in 1854 from parts of Baker and Early counties. It was named for Senator John C. Calhoun of South Carolina, who had resigned as Vice President of the U.S. in 1832 so that he could return to the Senate to debate Daniel Webster on state rights.
The county courthouse has burned down twice in Calhoun County, once in 1888 and again in 1920.
One site on the National Register of Historic Places is the Arlington Methodist Church, built in 1908. It was designed by Columbus architect T. Firth Lockwood, Sr., using the Romanesque style of architecture.
Morgan, the county seat, was named for General Daniel Morgan, a Revolutionary War figure.