In October 1665 he was naturalized to become an Englishman; then in 1667 he became the Keeper of the Privy Purse to the Duke of York. From 1667 until 1685 he was a Colonel of the Duke of York's Troop of Horse Guards, and from 1685 until 1689 of the first troop. On 29 January 1673 he was created Baron Duras of Holdenby. 
In 1675 he married Lady Mary Sondes, daughter of the 1st Earl of Feversham, but this marriage remained childless. When in 1677 his father-in-law died, he succeeded to the Earldom of Feversham. In 1677 and 1678 he was Ambassador in Paris, Lieutenant General of the Forces 
in 1678 and again in 1685, while in 1679 and 1680 he was Master of the Horse to Queen Catherine, the wife of King Charles II. In 1680 he became her Lord Chamberlain, which he remained until her death in 1705. 
From 1682 until 1688 he was Gentleman of the Bedchamber, first to King Charles II and then to King James II. On 6 July 1685, the Earl of Feversham was in command when the rebels were defeated at Sedgemoor, then on 25 August 1685 he was installed as a Knight of The Garter. 
After the Prince of Orange embarked for England, the Earl of Feversham was one of the few nobleman to offer their services to James II, and he was in command when the Prince of Orange took possession of Whitehall. In 1698 he became Master of St.Katherine's Hospital, which he remained until he died, of gout in the stomach, on 19 April 1709, and was buried in the French Chapel, Savoy, Middlesex. As he was childless, all his honours became extinct. Thomas, Earl of Ailesbury, described him as "A worthy man, but no great head or very great experience", and, according to Bishop Burnet: "He was a very dull old fellow." 
 

Source: Leo van de Pas