Mather Byles was born in Boston, Massachusetts, on 12 January 1735, the eldest child of the Rev. Mather Byles and Anna (Noyes) Gale. He had two younger sisters, Katherine and Mary. Mather Byles descended from a distinguished Puritan and staunch Loyalist background; his great-grandfather was the Rev. Increase Byles; his great-uncle, Jonathan Belcher, was the Colonial Governor and his father was a well-known congregational minister, poet and wit.

At the age of twelve, Mather Byles entered Harvard College and graduated in 1751. In 1754 he received an MA from Harvard and from Yale College in 1757. After two years as librarian of Harvard College, Byles was ordained in 1757 and became a congregational minister in New London, Connecticut. In 1768 he was converted to the Church of England and travelled to England where he received an Episcopal ordination from the Bishop of London. In 1770 he also obtained a DD from Oxford, England. On his return to America, Mather Byles took up duties as the minister of Christ Church, Boston and also as a missionary for the Society for the Propagation of the Gospel (SPG). In 1776, after a stormy relationship with his congregation, Byles resigned from his post as minister, and on the outbreak of hostilities in America, fled to Halifax with the British Troops where Byles served as chaplain to the garrison and as assistant to the rectors of St. Paul's Church.

Mather Byles was married three times; firstly to Rebecca Walter on 12 May 1761 in Roxbury (Boston); to Sarah Lyde on 10 February 1777 in Halifax (Nova Scotia) and thirdly to Susanna (Lawlor) Reid on 2 October 1788, also in Halifax. Byles fathered thirteen children from his first two marriages. In 1789 Mather Byles and his family moved to Saint John where he became rector of Trinity Church, a position in which he remained until early 1814 when he became blind. Mather Byles died in Saint John on 12 March 1814.

Source: Mather Byles Dictionary of Canadian Biography Vol V