In 1670 he received 3,000 acres of land from Charles II of England; a restoration of estates that had been seized from his father during the Cromwellian Conquest of Ireland.
[1] A Roman Catholic, Fitzgerald was accused of involvement in the Popish Plot in 1681 and was summoned to London.
[3] In September 1689 troops under Fitzgerald's command occupied Trinity College Dublin and seized the Great Book of Lecan.
In 1691, he was attainted and lost both his title and estate, leaving for France in November 1691 in the Flight of the Wild Geese.
He commanded the Régiment de Limerick of the Irish Brigade in French service and fought at the Battle of Landen in 1693.