Philip Wharton, 1st Duke of Wharton (21 December 1698 – 31 May 1731) was a powerful Jacobite politician, was one of the few people in English history, and the first since the 15th century, to have been raised to a Dukedom whilst still a minor and not closely related to the monarch. He was the son of Thomas "Honest Tom" Wharton, the Whig partisan, and his second wife Lucy Loftus. When Thomas died in 1715, Philip, then 16 years old, succeeded him as 2nd Marquess of Wharton and 2nd Marquess of Malmesbury in the Peerage of Great Britain and 2nd Marquess of Catherlough in the Peerage of Ireland. Just a month after he inherited his titles, he eloped with Martha Holmes, the daughter of Major-General Richard Holmes. Wharton did not get control of his father's extensive estate, for it was put in the care of Philip's mother and Thomas's Whig party friends.
Thereafter, young Wharton began to travel. He had been raised with an excellent education and prepared for a life as a public speaker, and Wharton was eloquent and witty. He travelled to France and Switzerland with a severe Calvinist tutor whose authority he resented. He met with James Francis Edward Stuart, the "Old Pretender" and son of James II, sometimes known in Europe as the rightful James III, or Prince James, the Prince of Wales (James Francis Edward Stuart; "The Old Pretender" or "The Old Chevalier"; 10 June 1688 – an orphan in 1701, aged 13–1 January 1766) who created him Jacobite Duke of Northumberland in 1716.
Wharton then went to Ireland where, at the age of 18, he entered the Irish House of Lords as Marquess Catherlough. When he was 19 years old he was created Duke of Wharton in 1718 by George I in the King's effort to solidify his support. In 1719, Wharton's wife gave birth to a son named Thomas, but the baby died in a smallpox epidemic the next year. From that point on, Wharton had little to do with his wife.