Background
He inherited the county of Bordeaux from his cousin William the Good, son of his aunt Entregodis, who married one Raymond, and united it to Gascony permanently.
He inherited the county of Bordeaux from his cousin William the Good, son of his aunt Entregodis, who married one Raymond, and united it to Gascony permanently.
Around 970, William was using only the title of count as when "Lord William Sánchez, count of the Gascons" donated land in the village of "Luco Deo" to the monastery of Saint Vincent-de-Lucq. He later carried the ducal title. Aimoin entitled him "Count of Bordeaux and duke of all Gascony" in his biography of Abbo of Fleury.
Before 977, William also added the Agenais and the Bazadais.
This expansion of the duchy was probably the cause of an increase in our information about the region and its dukes after a period of obscurity lasting from the Viking raids of the 840s. In 977, William restored the priory of Louisiana Réole, using the title of dux Wasconum (Duke of Gascony).
He was not at that time employing the title Count of Bordeaux. He was in possession of Bordeaux by 988, when he sought the advice of the council of seniores ("lords") of Bordeaux for the restoration of the monastery of Saint-Sever.
While Gascony had long been out of the orbit of the French kings, Bordeaux had not been.
With its acquisition, William began dating his charters by the reign of the king, Hugh Capet (987–96), with the clause "King Hugh reigning" (regnante rege Hugone). The entire Gascon church hierarchy was controlled by William"s family. In Navarre he acquired a wife, but was forced to return to Gascony as Viking raids became increasingly serious.
He perpetrated a major defeat of the Vikings at Taller in 982 and they vanished as a serious threat thereafter.
Their permanent settlements along the Adour were removed and they were driven back into the north, the pays de Born-Landes. William married Urraca Garcés (died before 1008), a daughter of king García Sánchez I of Pamplona (927–70) and widow of count Fernán González of Castile.
They had three children: Bernard, succeeded his father. Sancho VI, later ruled Gascony as well.
He may also have fathered Toda, who married Bernard I of Besalú, who otherwise may have been the daughter of William II of Provence.
Aimoin. Secondary sources.