Flacksenius, Johann a Lutheran theologian and prelate of Finland, was born at Mackyla in 1636. He studied at the University of Abo, of which he became secretary in 1665. Still later he was successively connected with the faculty of philosophy, professor of mathematics in 1669, and pastor in 1682. Finally he became bishop of Wiborg, and died July 11, 1708, leaving, among other works, Oratio Funebris in Abitum M. Andreae Thuronis, etc. (Abo, 1665): — De Ecclesia Ejusque Subjecto, etc. (1689): — Sylloge Systematum Theolgiae, etc. (ibid. 1690): — Chronologia Sacra (ibid. 1692): — Harmoniae Evangeliae (ibid. 1701). See Hoefer, Nouv. Biog. Generale, s.v.