Boso of Vienne

Boso (c. 841 – January 11, 887) was a Frankish nobleman of the Bosonid family who was related to the Carolingian dynasty and who rose to become King of Lower Burgundy and Provence.

Boso was the son of Bivin of Gorze, Count of Lotharingia, by Richildis of Arles, the daughter of Boso the Elder by his wife Engeltrude. His maternal aunt Teutberga was the wife of Lothair II, King of Lotharingia. Boso was also the nephew of the Boso, Count of Valois, for whom he was named, and of Hucbert, lay abbot of St. Maurice's Abbey, to which Boso succeeded in 869. He would later marry Ermengard of Italy, the daughter of Louis II of Italy and granddaughter of the Holy Roman Emperor Lothair I, whom he married at age 35.

In 870, Charles the Bald, King of West Francia, married Boso's sister Richilde. This marriage paved the way for Boso's career in the service of his royal brother-in-law. In the same year, Boso was appointed Count of Lyon and Vienne, replacing Gerard of Roussillon.

In 872, Charles appointed him chamberlain and magister ostiariorum (master of porters) to his heir Louis the Stammerer. Boso likewise received investiture as Count of Bourges. Louis was reigning as a subordinate king of Aquitaine, but because of his youth, it was Boso who looked after the administration of that realm.

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