Henry Mordaunt was born on 15 Nov 1621 and educated at Eton and in France. During the Civil War he switched sides from the Parliamentarians to the Royalists and was given command of a Troop of Horse. He was wounded at Nasby and fought at Cropredy and Lostwithiel. He joined the Earl of Holland's uprising in 1648 and escaped capture. After the Restoration he was back in favour and was appointed Captain General of Tangier but recalled to receive a pension after one year. He had financial worries but his friendship with James, Duke of York brought him brighter prospects. He was closely involved in the marriage of James to Mary of Modena and brought her to England. He converted to Catholicism and was later accused of complicity in the Popish Plot, but he redeemed himself by his involvement in the disclosure of the Rye House Plot in 1683 in which a plan was hatched by anti-Catholic republicans to ambush King Charles II and James Duke of York, and assassinate them.
He carried James's sceptre at the coronation and was made Knight of the Garter in 1685 along with his appointment as Colonel of the 3rd Regiment of Horse, and other high offices of the bedchamber etc. He was a close friend of King James and assisted in the purges of Protestant judges and Lords Lieutenant. In the Glorious Revolution his fortunes declined and his home in Northamptonshire was sacked by a mob. He was captured, imprisoned, and impeached by Parliament, but that was rescinded. The Earl was in his seventies when he was under house arrest for alleged involvement in a plot against King William's life in 1696. He became ill through eating oysters and never recovered; he died on 19 June 1697. His wife was Lady Penelope O'Brien, who he married in 1644. They had two daughters. Henry was a philanderer but behaved himself better in later life, being prone to humility and melancholy. The title of 3rd Earl of Peterborough passed to his nephew, Charles Mordaunt.
Regimental details | Colonels