The Monmouth Rebellion On July 15th 1685 James Scott, the Duke of Monmouth, was executed for treason against the King. He was a noble man who met his heath with calmness and dignity. James Scott, duke of Monmouth, byname (until 1663) James Fitzroy, or Crofts, (born April 9, 1649, Rotterdam, Netherlands—died July 15, 1685, London, England), claimant to the English throne who led an unsuccessful rebellion against King James II in 1685. The Monmouth Rebellion On the death of King Charles II on 6 February, 1685, his Catholic brother James, Duke of York succeeded to the throne as King James II. Charles II left no legitimate offspring but a large family of illegitimate sons and daughters by his many mistresses, the eldest of these was the Protestant James Scott, Duke of Monmouth.