Origin: Irish. The Strongbownian invaders added their Norman conventions for surnames to the previously established Irish system for hereditary surnames. One of the most frequent forms of surnames for both cultures was the patronymic surname, which was formed from the name of the bearer's father or grandfather. The Norman tradition that the followers of Strongbow brought with them created such a surname through diminutive suffixes such as -ot, -et, -un, -in, or -el. Occasionally, two suffixes were combined to form a double diminutive, as in the combinations of -el-in, -el-ot, -in-ot, and -et-in. The Normans also formed patronymic surnames in a manner very similar to the Irish: they added a prefix to their father's name. These Anglo-Norman people, however, used the prefix Fitz-, which was derived from the French word fils, and ultimately from the Latin filius, which both mean son. Although this prefix probably originated in Flanders or Normandy, it can now only be found in Ireland. The surname Fitzharris is derived from the personal name Henry, which was brought by the Normans into England and then Ireland. This name is composed of the elements haim or heim, which mean home, and ric, which means power. Harris was a patronymic form of Henry. The name features the distinctive Irish patronymic prefix fitz, which means son of in Anglo-French. This is derived from the Old French word fils, which ultimately comes from the Latin word filius. The Gaelic form of the surname Fitzharris is Mac Éinri. First found in county Wexford where they were granted lands by Strongbow on his invasion of Ireland in 1172.

Spelling variations include: Fitzhenry, Fitzharris, Fitzharrison and others.

Peter FitzHarrison & Elena Devereux y MacCabe ( modificado el 19.03.2017 )