William Wright Southgate (November 27, 1800 - December 26, 1849) was a Kentucky State and United States politician. He was the son of Richard Southgate and Ann Winston Hinde. He married Adaliza Keene of Lexington, Kentucky, on November 7, 1823, and they had 13 children.
William Wright was graduated from Transylvania University in Lexington. He moved to Covington, Kenton County, Kentucky, studied law and was admitted to the bar in 1821 and commenced practice in Lexington. He was a member of the Kentucky House of Representatives in 1827, 1832 and 1836. He was elected as a Whig to the Twenty-fifth Congress (March 4, 1837 - March 3, 1839). When he returned to Covington, he purchased the Thomas D. Carneal House (Covington's oldest and most elegant house). In 1840, he added a large wing to accommodate his growing family. He and Adaliza had thirteen children.
Southgate died in Covington on December 26, 1849. Services were held at the Masonic Hall in Covington and burial was in the Southgate vault in Linden Grove Cemetery. The Licking Valley Register (a local newspaper) said Southgate's unexpected death had "cast a gloom over the city such as we have never before witnessed".