Thomas Walker was born 1758 in Henbury, now a suburb of Bristol, England.
[2] 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.
[2] He 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.
[2] On 22 February 1785, Walker married Catherine McLelland (1770–1806) at St. Andrew's Church in Clifton.
[2] She 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, George E. Walker (1797–1864).