The Monmouth Rebellion,The Revolt of the West or The West Country rebellion of 1685, was an attempt to overthrow James II, who had become King of England, King of Scots and King of Ireland at 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, an illegitimate son of Charles II, claimed to be rightful heir to the throne and attempted to displace James II.
The rebellion ended with the defeat of Monmouth’s forces at the Battle of Sedgemoor on 6 July 1685. Monmouth was executed for treason on 15 July, and many of his supporters were executed or transported in the “Bloody Assizes” of Judge Jeffreys.

thanks Wikipedia