William I, Duke of Aquitaine

William was son of Bernard Plantapilosa and Ermengard. Sometime before 898, William married the Bosonid Angilberga, daughter of Boso of Provence and Ermengard of Italy.^[1]

By inheritance, William was the ruler of Auvergne and the Limousin. He conquered Poitou and Aquitaine in 893 on behalf of Ebalus Manser. He kept the latter for himself and was proclaimed duke. His possessions extended from Austrasia to Toulouse and included the Autunois and Mâconnais.

In 909, William founded the Benedictine abbey of Cluny that would become an important political and religious centre.^[2] William required no control over the abbey, which he arranged should be responsible directly to the pope (see Clunian reforms). This was especially striking since most monasteries were privately owned and the appointment of abbots and officials was left to that family or individual, leading to the appointment of untrained and unordained abbots and officials. William also nominated Cluny's first abbot, Berno of Baume.

A sign of William's independence of rule in Aquitaine is that he had a deniers minted in his own name at Brioude.^[3] He was buried in the monastery of Saint-Julien. William had no son who was able to succeed him^[2] and his nephew, William the Younger, son of his sister Adelinda, inherited his title.

William married Angilberga and they had:

• Boso

• Dukes of Aquitaine family tree

• Bouchard, Constance (2000). "Burgundy and Provence, 879-1032". In Reuter, Timothy (ed.). The New Cambridge Medieval History. Vol. III: c.900-c.1024. Cambridge University Press.
• Nouvelle Biographie Générale. Paris, 1859.
• Rouche, Michel. "Private life conquers state and society," in A History of Private Life, Vol. I, Paul Veyne, ed. Harvard University Press, 1987. ISBN 0-674-39974-9