Thomas Walker (1758–1797), also known as Beau Walker, was a British-American slave ship captain and resident slave trader who operated in the Sierra Leone region of West Africa. He did much of his slave trading at Bunce Island, a British slave castle in the Sierra Leone River, owned at that time by the Company of John & Alexander Anderson, based in London. Walker was involved in at least eleven slave trading voyages between 1784 and 1792, taking African captives from Sierra Leone to the British West Indies and the United States. He was the father of George E. Walker (1797–1864) and a direct ancestor of two U.S. presidents, both of whom have "Walker" as a middle name -- George Herbert Walker Bush and George Walker Bush.
He married Catherine McLelland on 22 February 1785, in St. Andrew's Church in Clifton. He was murdered in 1797 at sea in a mutiny. His wife Catherine, born in 1770, died on 18 October 1806, in Philadelphia, Pennsylvania, a decade after her husband, leaving their older son as the guardian for his sister and a younger son born the year his father was murdered.