It is located to the north of Poitou, and the residents are called Châtelleraudais.
Châtellerault was an important stronghold on the northern march of Poitou, established by the Count of Poitiers to secure his borders in the early 10th century. The count's local representative, the Vicomte de Châtellerault was established as a hereditary appointment by the time of Airaud who was probably a kinsman of the counts of Auvergne and dukes of Aquitaine; his heirs were vicomtes (viscounts) until the mid-11th century.
The daughter of Aymeric I, Ænor of Châtellerault (ca 1103 - ca 1130), whose mother had been the "mistress" in the new courtly love poetry of the troubadour lord William, sixth Count of Poitiers and ninth Duke of Aquitaine, who lodged in his tower the "Dangereuse de Châtellerault", married his son, William X of Aquitaine, and was mother of Eleanor of Aquitaine.
The title, Vicomte de Châtellerault, passed in turn to each of three great French noble families: La Rochefoucauld, Lusignan and, from the thirteenth century until the French Revolution, to the family of Harcourt.
However, in return for services offered to the Crowns of Scotland and France, the title of Duc de Châtellerault (1548) was presented to James Hamilton, 2nd Earl of Arran, Chief of the Name, and regent of Scotland during the infancy of Mary, Queen of Scots, and of France. This title, though now without any benefices, remains in contention between the heir male and the heir general of Arran, respectively the Duke of Abercorn and the Duke of Hamilton. (See Chatelherault Country Park, Lanarkshire.)