The Irish surname Toole is an anglicized form of the Gaelic name Ó Tuathail meaning “descendant of Tuathal,” an old Celtic personal name composed of the elements tuath meaning “people” and  gal meaning “mighty.” The Toole's were remarkable for their unremitting resistance to Anglo-Norman attempts to conquer Ireland from the late 12th Century down to the end of the 17th Century, and in 1171 Laurence O'Toole, though then Archbishop of Dublin, took up arms against the Anglo-Norman invaders. In 1220, some thirty-eight years after his death, he was canonized and is patron saint of Dublin. A branch of this great Leinster family established itself in Connaught at an early date, settling in Counties Galway and Mayo where the name is also widespread today.

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