Rev. Samuel W. Barnum, an 1841 graduate of Yale University, was made a "licenciate" of the New Haven West Association of the Congregational Church in 1844. He was minister of the Congregational Church of Granby, Connecticut from April 1849 to April 1850 and was listed as a member of the Massachusetts Home Missionary Society in 1849. He was ordained over the Congregational Church and Society of Chesterfield, Massachusetts on 25 Jan 1853. In The American Christian Record (1860) he was listed as a Congregational minister in Phillipston, Massachusetts.
He was the author of Vocabulary of English Rhymes (1876) and Romanism as it is (1877) and the editor of Smith's Comprehensive Dictionary of the Bible (1871; revised 1901).