Dr. Allen was born in Plymouth County, Massachusetts, of Puritan ancestry. The names of Alden, Standish, Pryor, Carey and Waldo appear in the family records. It is said that when four days old he "was carried across the village green to the meeting-house and dedicated to God in holy baptism." He graduated at Middlebury College, Vermont, in 1818. He at once evinced a preference for the Protestant Episcopal Church, and, coming to Maryland, became a lay reader at Trinity Church, West Marlboro', and studied for holy orders under Bishop Kemp. He was ordered deacon March 7, 1819, and priest 1821. After good service in St. John's, Prince George's County, and in Washington, D. C., the missionary spirit was so strong in him that he went to Ohio where he organized the Church in Dayton, 1830; Troy, 1831; Springfield, 1833; Hamilton, 1835, Trinity Church, Cincinnati, in 1844. In 1847 he returned to Maryland where he gave twenty-five years more of faithful service under the Bishop he loved, Bishop Whittingham. The closing years of his life were spent in Kentucky, where he died November 17, 1879, aged eighty-three years.