The FitzGeralds are one of the two greatest families that came to Ireland with the Anglo-Norman invasion in the 12th century. The name means simply 'son of Gerald' and may have its origins in Italy, with the medieval Gherardini family of Florence. They crossed Europe to settle in Wales and then came to Ireland in the 12th century.

There are two main divisions of the FitzGeralds: the Desmond branch and the Kildare branch. The name can be found in many parts of Ireland but is most numerous in counties Cork, Kerry, Kildare, and Limerick. Among the places associated with the FitzGeralds is Kilkea Castle, near Athy in Co. Kildare. It was once the residence of a branch of the FitzGeralds, the Dukes of Leinster, but is now a luxury hotel.

Glin Castle, eight miles west of Foynes, on the southern shores of the Shannon estuary, is open to the public. This is the seat of Desmond FitzGerald, 29th Knight of Glin, whose family has been in continuous possession of the castle for 700 years.