The Hauteville family, also called the Hauteville dynasty or House of Hauteville (French: Maison de Hauteville, Italian: Casa d'Altavilla), was a Norman family originally of seigneurial rank from the Cotentin. The Hautevilles rose to prominence through their part in the Norman conquest of southern Italy. By 1130, one of their number, Roger II, was made the first King of Sicily. His male-line descendants ruled Sicily until 1194. Some Italian Hautevilles took part in the First Crusade and the founding of the Principality of Antioch (1098).
The familial origins had roots from the Norsemen who had settled in Normandy in the 10th century. They are said to be descended from Hiallt, a Norseman who settled in the Cotentin Peninsula and founded the village of Hialtus Villa (Hauteville) from which the family takes its name. This eponymous Hiallt who gave his name to Hauteville may be legendary; Hauteville may simply mean "high town". Of several villages with the name "Hauteville", the one from which the family derived its name is hard to identify with certainty, though modern scholarship favours Hauteville-la-Guichard.
The first of the family well known to us is Tancred of Hauteville. He remained until his death (c. 1041) a minor baron of Normandy, but he had twelve sons and at least two daughters by two wives, Muriel and Fressenda. His small patrimony was hardly enough to satisfy his sons' desire for land and glory, and so eight of the twelve went south to the Mezzogiorno to seek their fortunes there.
According to Goffredo Malaterra's chronicle, the fourth son by Tancred's second wife, Fressenda, or Freisen, descendent from Frei, Avril, or Aubrey, was one Aubrey or Alverardus who remained behind in Normandy. About the time of the Domesday Book in 1086 a certain Alverardus or Aluericus Hautville (Halsvilla, Altavilla or Hauteville) is mentioned as having previously held lands in Compton Martin, Somerset, England. His kinsman Ralf de Hauville (also Halsvilla) is mentioned in the Domesday Book of 1086 as a tenant-in-chief in Burbage and Wolfhall in Wiltshire. Alverardus most probably founded the Somerset Hautevilles, and Ralf the Wiltshire/Berkshire Hauvilles.