Prince archbishop of Salzburg; b. Vienna, May 31, 1732; d. there May 20, 1812. This second son of Prince Rudolph Joseph studied at the Collegium Germanicum at Rome, became a canon of the cathedral at Salzburg (1747), prior of Kremsier in Moravia (1761), bishop of Gurk (1762), and after a drawn-out election prince bishop of Salzburg (1772). His main interest was his principality, whose well-being he sought to promote in every way. He raised the level of elementary education, patronized literary and artistic efforts, summoned German professors, and sent young noblemen to foreign universities. In Church history, however, he made a place for himself not as a secular ruler but as the prince archbishop of enlightened ideas. The program he developed in his famous pastoral letter of May 29, 1782, was met with complete approval by Emperor Joseph II and was translated into French and Italian. His reforms were aimed at a simple Christianity, purified of all incidentals and externals. They failed partly through opposition from conservative classes, but mostly because they were effected in haste and without sympathetic understanding of the mentality of the people. Colloredo did not vie for popular favor and even in exile sought to protect his episcopal rights as against the emperor. He was buried in St. Stephen's Cathedral.
Bibliography: j. c. allmayer-beck, Neue deutsche Biographie (Berlin 1953–) 3:327–328. j. mack, Die Reform– und Aufklärungsbestrebungen unter Colloredo (Munich 1912). j. schÖttl, Kirchliche Reformen des Salzburger Erzbischofs Hieronymus v. Colloredo im Zeitalter der Aufklärung (Hirschenhausen 1939). e. wolf, Die Religion in Geschichte und Gegenwart (3d ed. Tübingen 1957–65) 1:1851. f. loidl, Lexikon für Theologie und Kirche, ed. j. hofer and k. rahner (2d, new ed. Freiburg 1957–65) 3:5–6.