Noun
Williamite (plural Williamites)
(historical) A follower of King William III of England who deposed King James II in the Glorious Revolution.
Only warfare such as the Williamite War in Ireland and subsequent occupation enabled the English crown from 1692, and successive British states from 1707, to retain the country. Source: Internet
The Jacobites besieged Derry from December 1688 to July 1689, ending when a Williamite army from Britain relieved the city. Source: Internet