Despite his father taking great pains to educate him, and also using his influence to obtain various diplomatic appointments for what he hoped would be a high-flying career, Stanhope was treated with disdain by many, because of his illegitimacy. He was a Member of Parliament for Liskeard and St Germans. The government in 1764 wishing to get possession of his seat, asked him to vacate it, and after some negotiation he agreed, on receiving payment of £1,000, which was half the amount he had paid for it. He was also successively Resident at Hamburg, Envoy Extraordinary to the Diet of Ratisbon,, and finally on 3 April 1764 was appointed to the Court of Dresden, Saxony.
Family
Stanhope had met his wife Eugenia Peters in Rome in the spring of 1750, while on the Grand Tour. He was just 18, and she 20. Believed by many to be the illegitimate daughter of an Irish gentleman by the name of Domville, Eugenia was described by one observer as "plain almost to ugliness" although possessing "the most careful education and all the choicest accomplishments of her sex". Their two sons, Charles and Philip, were born in London in 1761 and 1763 respectively, and it was not until 25 September 1767 that he and Eugenia were married in Dresden. Stanhope went to great lengths to keep the relationship a secret from his father, to the extent of engaging a separate habitation for his wife and children. He had never lived up to the expectations of his father, unable to acquire the graces that Lord Chesterfield tried so hard to impart. He did not rise as expected in the Diplomatic services, preferring instead an unpretentious domestic life. Often in ill health, he died of dropsy in St Gervais, France on 16 November 1768, aged just 36, and is buried at Vaucluse. It was generally believed that only after the death of his beloved son did Lord Chesterfield learn of the existence of Philip's wife and children. He received them kindly and took upon himself the costof education and maintenance of his grandsons, becoming very attached to them. When Lord Chesterfield died in 1773, his will caused much gossip: while providing for the two grandsons – £100 annuity each, plus £10,000 – he left Eugenia Stanhope nothing. Faced with the problem of supporting herself, she sold Chesterfield's letters to a publisher for fifteen hundred guineas. Chesterfield had never intended them for publication and the result was a storm of controversy due to their perceived "immorality", which ensured several reprints, and their steady sale for at least the next one hundred years. Eugenia died at her home in Limpsfield, Surrey in 1783, having acquired property and a comfortable fortune. Eugenia also wrote The deportment of a married life: laid down in a series of letters, which was published in 1798. In a codicil to her will she directed her sons "to live in strict unity and friendship with one another, not to dissipate their fortunes and to beware of all human beings." Philip and Eugenia's sons were educated in the law. The elder son Philip married Elizabeth Daniel, had two daughters and died aged 38 in 1801. The survivor of his two daughters, Eugenia Keir, née Stanhope, died at Madeira in 1823, with no surviving issue. The younger son Charles died in 1845, aged 83 without issue, bequeathing most of his estate, which included Lord Chesterfield's bequests to both himself and his late brother, and his mother's properties, to the sons of Elizabeth Daniel's brother Edward Daniel, Barrister at Law.
