ARNOLF, bishop of Soissons. – A native of Brabant, he died at Altenburg on the vigil of the Assumption in 1087. After being a soldier, he became a monk at Saint-Médard in Soissons, and in 1081 was bishop of that city, where he encountered continual difficulties. As papal legate in Flanders from 1084, he founded the Benedictine monastery of Altenburg (Oudenburg).
BIBL.: The life of A., written by another abbot of Altenburg, Ariolfo, with the addition of a third book of miracles by Bishop Lisard of Soissons, was read at the Council of Beauvais in 1120. – J. Mabillon, Acta SS. Ordinis s. B., IX, 11, Paris 1701, pp. 502-57; Acta SS. Augusti, III, Antwerp 1737, pp. 221-259; Martyr. Romanum, p. 340; PL 174, 1371-80; BHL, I, Brussels 1898-99, no. 704.