As described in historical dictionaries

Patronymica Britannica (1860)

COSTELLO. Among the many ANorm. settlers in Ireland, temp. Henry II., was Hostilio de Angulo. His descendants were called Mac-Ostello (son of Hostilio) which by still further corruption became Costello.

Lower, Mark A (1860) Patronymica Britannica: a dictionary of the family names of the United Kingdom. London: J.R. Smith. Public Domain.


Origin: Celtic

Region of origin: British Isles

Country of origin: Ireland

Religion of origin: Christian

Language of origin: Gaelic

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