William Sommerville was born in Ballyroney, County Down, Ireland, July 1, 1800. He studied classics and graduated with honors from the University of Glasgow, Scotland, in 1820. He was licensed by the Southern Presbytery, Ireland, in 1826. He was ordained sine titulo by the Southern Presbytery, Ireland, May 31, 1831, as a missionary to the British North American provinces (now Canada) and sailed for St. John, New Brunswick, in August of that year. There he labored amongst scattered Presbyterians until a congregation of Covenanters was organized in 1833. Sommerville labored for 47 years as a missionary. In 1835, he was installed as pastor of the united congregations of Horton and Cornwallis, Nova Scotia. He was noted for his controversies with the Baptists and hymn-singers, writing several pieces on both subjects. His book on the “Exclusive Use of the Psalms of David” (1855) was initially published in a shorter form in 1835 and is a most capable defense of psalmody. He died at his home in Somerset, Nova Scotia, September 28, 1878.