Thomas Leyland (c.1752-1827) was a merchant, banker, millionaire and three times Mayor of Liverpool. In 1766 he won a lottery prize of £20,000, which he used to build up his business affairs. He was involved in various trading partnerships. He built up much of his mercantile fortune from participation in the slave trade, and was particularly active in that traffic as well in various other trades in the last two decades of the eighteenth century. Leyland had an interest in sixty-nine slaving voyages from Liverpool. The ships in which he was concerned delivered an estimated 22,365 Africans to the Americas. He was associated with some other important Liverpool merchants but he also linked up with smaller fry. Thus, for example, he was part owner with David Tuohy in the slave ship Kitty in 1789. In 1802 Leyland entered into a banking partnership with Clarke and Roscoe, a firm of Liverpool bankers. After this was dissolved in 1806, he set up his own bank in Liverpool with his nephew Richard Bullin in 1807. Through amalgamations, his banking business later became part of the Midland (now HSBC) Bank. Thomas Leyland left a fortune of £600,000 in 1827, making him one of the wealthiest decedents in Britain at the time. In addition to the records made available here, further documents relating to Leyland’s slave trading and banking career survive in the HSBC archives and among the Dumbell Papers at Liverpool University Library. A good many of Leyland’s ships’ books relating to the slave trade were unfortunately destroyed by bomb damage during the Second World War.