In 1689, he was summoned to the Irish House of Lords as Baron Maguire of Enniskillen in the brief Patriot Parliament called by James II of England.
Maguire subsequently raised his own Jacobite regiment in the Williamite War in Ireland and he fought at the Battle of Aughrim.
After the Siege of Limerick, Maguire was attainted and joined in the Flight of the Wild Geese to France.
However, no command was assigned to him in France and Maguire retired to the exiled Jacobite court at Château de Saint-Germain-en-Laye, where he died in 1708.
[3] Maguire had married Mary, daughter of Philip MacHugh O'Reilly, and he was succeeded by his son, Alexander, who died in France in 1719.