he name Power is originally Norman. It may have come from the old French word poore, meaning poor, or from Pohier, meaning a native of the town of Pois, in Picardy, France. The Powers came to Ireland in the 12th century with the Anglo-Norman invasion, and the clan became among the most Hibernicised of all the Anglo-Norman families. Today, it is principally found in and around Co. Waterford.

Among the places associated with the name is Curraghmore House, near Kilmacthomas in west Waterford. In the 18th century, James Power, Earl of Tyrone, rebuilt the house and laid out gardens on a scale to match Versailles. The 8th Marquis of Waterford still lives in Curraghmore House, a treasure trove of Power family history.

The estate at Powerscourt, near Enniskerry in Co. Wicklow, was originally granted to a Norman knight, Eustace le Poer, after the Anglo-Norman invasion. A cas tle was built there by William Power, probably in the 15th century, which was demolished to make way for Powerscourt House in the 18th century.