The clay soil of the area, first cultivated by Creek Indians, gave this agricultural community it name in 1878 when a post office was established. Clay's historical roots date to the early 1800s through two small communities, Ayres and Self's Beat, documented by the founding of Mount Calvary Presbyterian Church around 1806 and Cedar Mountain Church (now Clay United Methodist Church) in 1819. In early years, the community was a stagecoach stop along the route from Elyton (now part of Birmingham) to Gadsden.
Lying in the Appalachian foothills, Clay is cherished for its environmental beauty, history, and landmarks. It is uniquely positioned in three watershed basin: the Black Warrior, Cahaba and Coosa. The Cahaba, Alabama's longest free-flowing river, originates from springs just northeast of Clay. Clay is home to Butler Mountain, Jefferson County's highest elevation. Incorporated in June 2000, Clay now includes Chalkville and its rich heritage, including Taylor Memorial United Methodist Church established in 1819.