As described in historical dictionaries

Patronymica Britannica (1860)

MAC GAWLEY. A corruption of Mac Awley. The head of the house was chief of Calrigia on the borders of Westmeath and King's County. The lineage is traced from Manie, the fourth son of Niall of the Nine Hostages; but so far as Mr. D'Alton's account goes, the first person that occurs of this surname is Aireachtach Mac Awley, chief of Calrigia, who died in 1187.

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


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