William Carroll (1788–1844) was Governor of Tennessee from 1821 to 1827 and again from 1829 to 1835. He and John Sevier are the only two persons to serve twelve years in that office.

Like two of his predecessors, Archibald Roane and Joseph McMinn, Caroll was a native of Pennsylvania. He came to Tennessee at the age of eighteen, and enjoyed considerable success in business prior to joining the militia in active service under Andrew Jackson in the War of 1812. He was a successful and popular soldier, and used this and his relationship with Jackson to launch his political career. Like his mentor he was a Democrat.

His governorship was noted for the establishment of a more progressive (for the era) Penal Code and the establishment of Chancery Court . Term limits prevented him from serving over three terms consecutively and in 1827 he was succeeded by Samuel Houston; after Houston resigned as governor, Caroll sucessfully sought the office again and served three additional terms. During his final term the state constitution of 1796 was supplanted by a new one which gave more executive power to the governor; although this document was technically superseded by the current one in 1870, that document carries over very many of the provisions of the 1834 constitution, upon which it was largely based. Carroll served as governor of Tennessee longer than anyone else has to this point, even fellow six-term governor Sevier. Sevier's first term was unusually short due to the time of year of the admission of Tennessee into the Union. Caroll's gubernatiorial service totalled twelve years and twelve days.

Carroll lived quietly after his terms as governor ended. Carroll County, Tennessee is named in his honor.