DEUSDEDIT. - Originally from Limousin, he was probably a Benedictine monk, already a cardinal in 1078, and died between 1097 and 1100. He was one of the strongest supporters of the Gregorian reform and exerted considerable influence on the movement to secure the supremacy of the Roman pontiff, the restoration of clerical celibacy, and the suppression of simony.
To this end, he composed his principal work, the Collectio canonum (1083-87). It contains 1,173 fragments, which reveal the privileged position of the Roman Church; besides canons from general and particular councils, passages from the Fathers and papal documents, it includes numerous texts of Roman law, drawn especially from the Authenticum, the collection of Justinian's Novels, which had been recently discovered.
Another of his works is the Libellus contra invasores et sym-monicos (1088-93), written in connection with the issues raised by the ordinations conferred by the antipope Clement III; however, his thesis was not approved by the Council of Piacenza.
He was also erroneously attributed with the authorship of the Dictatus Papae.