He studied at Paris and Bologna, and, having been successively archpriest of St Peter's, papal chaplain, cardinal-deacon of Sant' Eustachio, cardinal-bishop of Ostia, the first protector of the Franciscan order, and papal legate in Germany under Innocent III., and Honorius III., he succeeded the latter in the papacy.
In the Lutheran Church in Germany the title archpriest (Erzpriester) was in some cases long retained as the equivalent of that of superintendent, sometimes also still called dean (Dechant), his functions being much the same as those of the rural dean.
Under the bishops the affairs of the dioceses are managed by archdeacons (q.v.) and rural deans (see Archpriest and Dean).
In Rome itself, as the office of archdeacon grew into that of cardinal-camerlengo, so that of archpriest of St Peter's developed into that of the cardinal-vicar.
Out of these developed the rural deaneries, the office of archpriest being ultimately merged in that of rural dean, with which it became synonymous.