The Monmouth Rebellion, also known as the Pitchfork Rebellion, the Revolt of the West or the West Country rebellion, was an attempt to overthrow James II. He had become king of England, Scotland, and Ireland upon the death of his elder brother Charles II on 6 February 1685. James II was a Roman Catholic and some Protestants under his rule opposed his kingship. James Scott, 1st Duke of Monmouth, the eldest illegitimate son of Charles II, claimed the throne in an attempt to displace his uncle.

Plans were discussed to overthrow the king following the failure of the Rye House Plot to assassinate Charles II and James in 1683, while Monmouth was in self-imposed exile in the Dutch Republic. The Monmouth rebellion was coordinated with Argyll's Rising, a rebellion in Scotland, where Archibald Campbell, 9th Earl of Argyll, landed with a small force. The Duke of Monmouth had been popular in the South West of England, so he planned to recruit troops locally and take control of the area before marching on London.

Monmouth landed at Lyme Regis on 11 June 1685. In the following few weeks, his growing army of nonconformists, artisans and farm workers fought a series of skirmishes with local militias and regular soldiers commanded by Louis de Duras, 2nd Earl of Feversham, and John Churchill. Monmouth's forces were unable to compete with the regular army and failed to capture the city of Bristol. The rebellion ended with the defeat of Monmouth's army at the Battle of Sedgemoor on 6 July 1685 by forces led by Feversham and Churchill.

Monmouth was beheaded for treason on 15 July 1685. Many of his supporters were tried during the Bloody Assizes, led by Judge Jeffreys, and were condemned to death or transportation. James II was able to consolidate his power and reigned until 1688, when he was deposed by another nephew, William III of Orange, in the Glorious Revolution.