The Williamite War in Ireland

William III, Prince of Orange, came from a Dutch family that had become champions of Protestantism in Europe. He invaded England in 1688 and released a manifesto calling for the liberation of the country from the rule of the Catholic King James II. Supporters of James II were called Jacobites, but they were in a small minority in England. Jacobites were more numerous in Ireland and Scotland.

Because King James II had very little support in England, William's invasion caused relatively little conflict there. It is sometimes referred to as the Glorious Revolution. Realising he was effectively defeated by William's political skill, James fled England in fear of his life. William was then installed as King.

King William landed in Ireland on 14 June 1690 in order to attempt to defeat the Jacobites. He brought a large army of 36,000 men, which was by far the biggest ever seen in Ireland. They fought the army of King James at the River Boyne. The famous Battle of the Boyne began on 1 July when King William's army pounded the Jacobites with guns at dawn.

Due to greater numbers and firepower, King William won the battle. The Jacobites, who were French and Irish, withdrew to defend the Shannon. On 11 August, Patrick Sarsfield destroyed much of William's siege train and William abandoned his attack on Limerick. He left Baron de Ginkel in charge of continuing the war in Ireland against the Jacobites, who were eventually defeated.

The Treaty of Limerick was signed on 3 October 1691. As part of the deal, Sarsfield led 15,000 men to France. There they served in the army of King Louis XIV.