Tancred of Hauteville was an eleventh-century Norman petty lord about whom little is known. His historical importance comes entirely from the accomplishments of his sons and later descendants. He was a minor noble near Coutances in the Cotentin, but it is not even certain which of the three villages called Hauteville he held, though Hauteville-la-Guichard is most often cited. Various legends later arose about him which have no supporting contemporary evidence. He had 12 sons by his two wives, and several daughters, almost all of whom left Normandy for southern Italy and acquired some prominence there. By his first wife Muriella he had five sons:
- William Iron-Arm, count of Apulia (1042-1046)
- Drogo, count of Apulia (1046-1051)
- Humphrey, count of Apulia (1051-1057)
- Geoffrey, count of Loritello
- Serlo (stayed in Normandy), lord of Hauteville (1041)
According to the Italian chronicler of the Norman feats in the south, Amatus of Montecassino, Tancred was a morally upright man who would not carry on a sinful relationship and so remarried, being unable also to live out his life in perfect celibacy. By his second wife Fressenda (or Fredesenda) he had seven sons and at least one daughter:
- Robert Guiscard, count of Apulia (1057), then duke of Apulia and Sicily (1059-1085)
- Mauger, count of the Capitanate (1056-1059)
- William (Willerm or Guillerm, Willermus in Latin), count of the Principate
- Aubrey (Alberic or Alvared, Alveredus in Latin; sometimes called Alvred or Alfred) (stayed in Normandy)
- Humbert (Hubert) (stayed in Normandy)
- Tancred (stayed in Normandy)
- Roger, count of Sicily from 1062
- Fressenda, who married Richard I (dead in 1078), count of Aversa and prince of Capua
