Alfonso of Hauteville

Alfonso, also called Anfuso or Anfusus (c. 1120 – 10 October 1144), was the Prince of Capua from 1135 and Duke of Naples from 1139. He was an Italian-born Norman of the noble Hauteville family. After 1130, when his father Roger became King of Sicily, he was the third in line to the throne; second in line after the death of an older brother in 1138. He was the first Hauteville prince of Capua after his father conquered the principality from the rival Norman Drengot family. He was also the first Norman duke of Naples after the duchy fell vacant on the death of the last Greek duke. He also expanded his family's power northwards, claiming lands also claimed by the Papacy, although he was technically a vassal of the Pope for his principality of Capua.

Alfonso was the third son of Count Roger II of Sicily, who became king in 1130, and his first wife, Elvira of Castile. He was probably named after his maternal grandfather, King Alfonso VI of Castile, but contemporary sources invariably use the spellings Anfusus, Anphusus or Amphusus. According to Alexander of Telese, in August 1135 Alfonso was a mere "boy" (puer) too young to be knighted alongside his brothers Roger (died 1148) and Tancred (died 1138). While the Latin term puer might refer to a man up to the age of 28, Alfonso was less than sixteen years old, the age at which a boy was knighted in medieval Sicily. He was also older than two other brothers, William and Henry, described as infantes (infants), that is, under fourteen. Alfonso's birth therefore took place around 1120.

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