Abbot of Hirschau, monastic reformer, born in Bavaria; died at Hirschau, 5 July 1091. He was educated and took the Benedictine habit at Saint Emmeram, Ratisbon. In 1069 he was called to Hirschau to succeed the deposed Abbot Frederick. He at once assumed the management of the monastery, but would not accept the abbatial benediction till after the death of his unjustly deposed predecessor in 1071. Under William’s abbacy, Hirschau reached the zenith of its glory and, despite the unusually strict monastic discipline which he introduced from Cluny, the number of priest-monks increased from 15 to 150. He was the first to introduce lay brothers (fratres laici, also called conversi, barbati, or exteriores) into the German Benedictine monasteries. Before his time there were, indeed, men-servants engaged at the monasteries, but they lived outside the monastery, wore no religious garb, and took no vows. In 1075 William went to Rome to obtain the papal confirmation for the exemption of Hirschau. On this occasion he became acquainted with Gregory VII, with whose reformatory labours he was in deep sympathy and whom he afterwards strongly supported in the great conflict with Henry IV. William had received an excellent education at St. Emmeram, and in the knowledge of the quadrivials he was unsurpassed in his time. He constructed various astronomical instruments, made a sun-dial which showed the variations of the heavenly bodies, the solstices, equinoxes, and other sidereal phenomena. He was also a skilled musician and made various improvements on the flute. Besides composing the “Constitutiones Hirsaugienses”, he is the author of a treatise “De astronomia”, of which only the prologue is printed, and “De musica”. William also had a standard edition of the Vulgate made for all the monasteries of the Hirschau reform. He is commemorated in various martyrologies on 4 of 5 July.
- Michael Ott. “Blessed William”. . CatholicSaints.Info. 20 December 2015. Web. 27 April 2017. <>