Williamite forces defeated the Jacobites at the Battle of Aughrim, the decisive battle of the Williamite War in Ireland.

A Williamite was a follower of King William III of England who deposed King James II and VII in the Glorious Revolution. William, the Stadtholder of the Dutch Republic, replaced James with the support of English Whigs.

Jacobitism was a political ideology advocating the restoration of the senior line of the House of Stuart to the British throne. When James II of England chose exile after the November 1688 Glorious Revolution, the Parliament of England ruled he had "abandoned" the English throne, which was given to his Protestant daughter Mary II of England, and his nephew, her husband William III. On the same basis, in April the Scottish Convention awarded Mary and William the throne of Scotland.

The Battle of Aughrim was the decisive battle of the Williamite War in Ireland. It was fought between the largely Irish Jacobite army loyal to James II and the forces of William III on 12 July 1691, near the village of Aughrim, County Galway.

The Williamite War in Ireland took place from March 1689 to October 1691. Fought between Jacobite supporters of James II and those of his successor, William III, it resulted in a Williamite victory. It is generally viewed as a related conflict of the 1688 to 1697 Nine Years' War.