Wikipedia
The Ramnulfids, or the House of Poitiers, were a French dynasty ruling the County of Poitou and Duchy of Aquitaine in the 9th through 12th centuries. Their power base shifted from Toulouse to Poitou. In the early 10th century, they contested the dominance of northern Aquitaine and the ducal title to the whole with the House of Auvergne. In 1032, they inherited the Duchy of Gascony, thus uniting it with Aquitaine. By the end of the 11th century they were the dominant power in the southwestern third of France. The founder of the family was Ramnulf I, who became count in 835.
Ramnulf's son, Ramnulf II, claimed the title of King of Aquitaine in 888, but it did not survive him. Through his illegitimate son Ebalus he fathered the line of dukes of Aquitaine that would rule continuously from 927 to 1204, from the succession of William III to the death of Eleanor, who brought the Ramnulfid inheritance first to Louis VII of France and then to Henry II of England.
Several daughters of this house achieved high status. Adelaide married Hugh Capet and was thus the first Queen of France in the era of the Direct Capetians. Agnes married Henry III, Holy Roman Emperor, and ruled as regent for her son, the young Henry IV. The most illustrious woman was certainly Aquitaine's ruler Eleanor, whose marriage to Henry II of England crafted the Angevin Empire which was to cause so much discord between France and England.
The Ramnulfid house did much to encourage art, literature, and piety. Under William V, William IX, and William X, Aquitaine became the centre for the art of poetry and song in the vernacular; the troubadour tradition was born and raised there. The Peace and Truce of God were fostered and the ideal of courtly love invented.