The first WM missionary to Australia and New Zealand, he was born on 1 September 1782 at Milton, Stoke on Trent, and trained at the Gosport Congregational seminary. He went to New South Wales in 1815 to an itinerant ministry based in Sydney, but extending over 150 miles. On 7 October 1817 he opened the first Methodist chapel in the southern hemisphere at Castlereagh (soon replaced by a larger building, and again in 1848 by a stone-built church which was still surviving in 1992).
He found it difficult to work with his colleague Walter Lawry, but established a close relationship with the Anglican chaplain Samuel Marsden, who enabled him in 1819 to recuperate his health by a voyage to New Zealand. Back in England in 1820, recovering from his exhausting labours, he successfully advocated a mission to New Zealand and was appointed to return there. By 1823 he had established the ill-fated 'Wesleydale' mission at Kaeo on Whangaroa Bay. He maintained good relations with the CMS staff at the Bay of Islands. Of undoubted abilities, but unable to husband his energies, he was obliged to return to Sydney in 1825 and to English circuit work in 1831.
Leigh died in Reading on 2 May 1852. Leigh Memorial church, Milton and anotherof that name at Parramatta in New South Wales were built to honour his name.