a German theologian, was born at Chemnitz, in Saxony, Sept. 16,1786, studied at the University of Leipzig, where he first lectured, and then became extraordinary professor of philology in 1818, of theology in 1823, ordinary professor of theology in 1825, and finally canon. He was particularly distinguished for his knowledge of theological history. He died Aug. 4, 1844. His principal works are, Lalius Socinus, Leben (Lpz. 1814 and 1826, 2 parts,. 4to): — Memoria utriusque catechismi Lutheri (Leipzig, 1829-30): — Historia collegi iphilobiblici (1836-40): — Abhandlung i. den Wlerth der christlichen Dogmengeschichte (1817); and a collection of Predigten: die Veirlarung d. irdischen Lebens durch d. Evangelium (1823). He founded the Historical Theological Society, and from 1825 to the time of his death he edited the Zeitschriffiur hist. Theol. See S. Bruno Lindner, Erinnerungen an Dr. Illgen in the Zeitschrift.f. d. historische Theologie (1845), p. 3; Hoefer, Nouv. Biog. Gé neralé. 25, 814; Herzog, Real Encyklopadie, 6, 635.