UBALDO of SANT'AMANDO. - Learned monk (Hucbaldus, Hubaldus, Hugbaldus, Hucboldus, Uchubaldus), born ca. 830, entered the Benedictine abbey of St Amandus (famous "Monasterium Elnonense" in Gallic Flanders), where he died on 20 June 930.
He was educated by his learned uncle Milo in the same abbey and furthered his knowledge of the sciences and letters at Nevers (?) and Auxerre in France. His rare literary, theological, and especially musical learning, combined with outstanding religious virtues, led to his appointment (ca. 872) as director of the school at St Amandus; then (883) he directed the school of the abbey of St Bertin near St-Omer; and finally (893) that of Reims, whither he went at the request of Archbishop Fulco. Around the year 900 he returned to the abbey of St Amandus. He was on friendly terms with the great scholars and men of letters of his time.
Besides some verse compositions and the *Acta martyrii ss. Ciriaci et Julitiae* (apocryphal), he left various hagiographical works of great value, such as the lives of St Rictrudis, St Aldegundis, and other biographies of Flemish saints of the 7th century. His writings on music are important for the history of that art in that century; but the authenticity of several of them is disputed. The *De harmonica institutione* (M. Gerbert, *Scriptores de musica sacra*, I, St Blaise 1784, pp. 104-105) seems to be his, in which, while drawing on earlier works, he provides valuable information on the notation of intervals, etc.