GISELHER of SLATHEIM. — Dominican mystic of the 14th century. A native of Slatheim or Scholtheim, northwest of Erfurt, G. was a lector in Cologne and Erfurt, distinguishing himself through learning, priestly zeal, and stylistic expression. From 1323 to 1337 he compiled a German collection of sermons on the Sunday Gospels, some of which were printed.
G. insists on the birth of the Word; he refers to the preachers who spoke in the same milieu on subjects of mysticism and future glorification; he refutes the theses of the Franciscans. He provided the layman Hermann of Fritzlar, for his legend, with the substance of the lives of the saints according to the liturgical cycle.
BIBL.: G.W. Preezer, Gesch. der deutschen Mystik im Mittelalter, II, Leipzig 1881, pp. 99 ff.; E. Krebs, s. V. in Stammers Verfasserslexikon, II, col. 52, with bibliography.