William IX of Aquitaine (October 22 1071 - February 10 1126, also Guillaume d'Aquitaine), nicknamed the Troubador was Duke of Aquitaine and Gascony and Count of Poitiers between 1086 and 1126. He was also one of the leaders of the First Crusade and one of the first vernacular poets and troubadors.
Family
William was the son of William VIII of Aquitaine by his wife Hildegard of Burgundy. He was briefly married to Ermengarde of Anjou, before taking as wife Philippa of Toulouse. From Philippa William had:
Agnes of Poitiers, who married to king Ramiro II of Aragon
William, count of Valentinois
Henry, abbot of Cluny
Raymond of Poitiers, ruler of the principality of Antioch, a crusader state
William X of Aquitaine, his heir.
William is also known for his affair with Dangerosa, the wife of his vassal Aimery I de Rochefoucauld, Viscount of Ch tellerault. It was Dangerosa's daughter by Aimery, Aenor, who would eventually marry William's son, William X of Aquitaine, and give birth to Eleanor of Aquitaine.
Military life
William of Aquitaine joined the first Crusade led by Godfrey of Bouillon, Robert of Normandy and Raymond of Toulouse only after the fall of Jerusalem in 1099. He arrived in the Holy land in 1101 and stayed there until the following year. His record as a general is not very impressive. William fought mostly skirmishes in Anatolia and was frequently defeated. His recklessness had his army ambushed on several occasions, with great losses to his own side. Later on in his life, William joined forces with the kingdoms of Castile (an old ally and his younger sister Beatrice had been the last of the wives of Alfonso VI of Castile) and L on. Between 1120 and 1123, Aquitanian troops fought side by side with queen Urraca of Castile, in an effort to conquer the Moors of Cordoba and complete the Reconquista. William IX also provided troops to Philip I of France in his war against William the Conqueror.
Poetry
William's greatest legacy to history was not as a warrior but as a man of the arts. He was one of the first European lyric poets and used vernacular language in his songs and poems. His artistic name was Guilhem de Peitieus, and he was one of the most important troubadours of the Middle Age's Proven al literature. The topics of these were very diverse, but the majority is about sex, love and women and often about his own sexual prowesses. This choice of subject in a world used to music only for the praise of God and heroes caused scandal and admiration at the same time. In the next few years, troubadors and vernacular poetry would be fashionable and the most important artistic movement of the Middle Ages. William was a man that loved scandal and with no doubt enjoyed shocking his audiences. In the return from the crusade, he repudiated his wife in favour of a married woman, known as Dangereuse from his poems, and faced the risk of excommunication for the deed. He also fancied the idea of constructing a convent in his lands, where the nuns would be picked among the most beautiful women in the region. The fake nunnery project was abandoned and William ended by giving enormous donations to the church, perhaps to regain the pope's favour. He also constructed the palace of Poitou.