Duke of Monmouth
Also known as James Scott. Born in 1649 in Rotterdam, Netherlands. Died in 1685 in London, England. He was the illegitimate son of King Charles II and his mistress Lucy Walter.
Charles and Lucy met in Netherland during Charles's exile from the English Civil War. Although the two had no contact whatsoever after James's birth, Lucy wanted to proof that she was indeed the king's wife. Rumours about a 'Black Box', in which government officials could find the lost marriage certificates, swirled around. However, after Charles married Catherine of Braganza in 1662, he declared that such a marriage contract never existed.
Despite the issues he had with his mistress, Charles stood behind his illegitimate bastard child. In 1658, James was removed from his mother's care and brought up by Lord William Crofts. In 1662, two years after his father successfully succeeded to the English throne, James travelled to Charles II's court and was made Duke of Monmouth on Feburary 14, 1663. Charles wanted his son to be accepted at court and arranged a marriage between James and the twelve-year old Scottish Anne Scott, Countess of Buccleuch, whose surname James assumed.
Since Charles and his wife Catherine had no legitimate children of their own, the traditional concept of primogeniture could not be applied to this particular situation. Charles's brother James, Duke of York, was the obvious heir to the throne, but he was a supporter of Catholicism, a religion that was mainly associated with violence and superstition among many people in England. James Scott, on the other hand, was raised as an Anglican Protestant who had the ability to fascinate people. Unfortunately, he cooperated with the wrong political party: the anti-Catholic Whigs pushed him into thinking that he was indeed the legitimate son and heir of Charles II. Their support and influence turned James into a staunch megalomaniac. Between 1682-83, James became part of the Rye House Plot and his father forced him to leave England in 1684. On his deathbed, Charles II revealed himself as a Christian and handed his legacy over to his Catholic brother James, now King James II. In 1685, James Scott, who still believed that he had the divine right to declare himself king of England, arrived at Dorset, England, where he and his 4,000 followers unsuccessfully defeated his uncle's troops in the Battle of Sedgemoor. James Scott was arrested and beheaded soon afterwards.
Sources: http://www.britannica.com/EBchecked/topic/389635/James-Scott-duke-of-Monmouth
http://englishhistoryauthors.blogspot.de/2013/01/the-protestant-prince-james-scott-duke.html
http://www.spartacus.schoolnet.co.uk/STUmonmouthD.htm
http://unusualhistoricals.blogspot.de/2012/10/executed-james-scott-duke-of-monmouth.html