composition the Stanhopes returned to England, and Mahon threw himself with ardour into politics.
Early in September 1774 he was presented at court, and as his father would not allow him to wear powder 'because wheat is so dear,' he went in his natural 'coal-black hair' and a white feather. The wits said 'he had been tarred and feathered' (Walpole, Letters, vi. 114). A few weeks later, when only just of age, he contested the city of Westminster, but, after the poll had been open for some days, withdrew. At this time he was inspired with an ardent friendship for the second William Pitt, who was then equally ardent for reform, and their alliance was cemented by his marriage, on 19 Dec. 1774, to his friend's sister, Lady Hester Pitt, elder daughter of the first Earl of Chatham. Lady Mahon died at the family seat of Chevening, Kent, on 18 July 1780, when only twenty-five.
During the Gordon riots of June 1780 Mahon harangued the people from the balcony of a coffee-house, and urged them to retire to their homes. Walpole said that he 'chiefly contributed by his harangues to conjure down the tempest' (Letters, vii. 377-81). On the following 6 Sept. he was elected, through the influence of the Earl of Shelburne, member for the borough of Chipping Wycombe in Buckinghamshire, and represented it until his accession to the peerage. At the opening debate (October 1780) on the choice of speaker, he made his maiden speech, and in 1781 he was a delegate for the county of Kent to advocate the cessation of the American war and the promotion of parliamentary reform. From 1782 to 1786 he introduced into the House of Commons several bills for the prevention of bribery and corruption and for the reduction of expenses at parliamentary elections. The provisions of his bill against bribery were declared by Lord Mansfield on 23 March 1784 to be already part of the law of the land (Gent. Mag. 1784 i. 229). His bill for annual registration of voters, for increase in the number of polling places, and for other improvements at elections was taken charge of after he had become a peer by Wilberforce, and, with Pitt as its friend, passed the commons, but was thrown out by the lords on 5 July 1786.
Mahon had associated himself with the whigs in their opposition to the war with the American colonies, but he strongly opposed the coalition of Fox and North, and he was vehement against Fox's East India Bill. He declined office on the formation of Pitt's cabinet in 1783, but remained for a short time his strenuous supporter. At the general election in 1784 he laboured in the interest of Pitt. Walpole at the time dubbed him 'a savage, a republican, a royalist I don't know what not' (Letters, viii. 469). He spoke at the meetings of the electors of Westminster in February 1784 against Fox and the coalition (cf. Jephson, The Platform, i. 155-6). His first political difference with Pitt took place on 22 July 1784 over the tax on bricks and tiles. He ridiculed the arguments of George Rose (1744-1818) [q.v.] in its favour, and Pitt rallied him ironically in return.
On 7 March 1786 he succeeded to the peerage as the third Earl Stanhope, and lost no time in attacking by speech and pamphlet Pitt's proposals for a sinking fund. His pamphlet was entitled 'Observations on Mr. Pitt's Plan for the Reduction of the National Debt,' and Pitt tried hard to dissuade him from its publication (Lord Auckland, Journal, i. 369). Two bills were introduced by him into the House of Lords in the summer of 1789. One was for relieving members of the church of England from sundry penalties and disabilities; the other was for preventing vexatious proceedings for the recovery of tithes. Both were thrown out, the first on 18 May, the second on 3 July, and on the first date he created much amusement by informing the lord chancellor that 'on another occasion I shall teach the noble and learned lord law, as I have this day taught the bench of bishops religion.' He was accordingly represented in caricature as a schoolmaster, with a rod in his hand. His speeches abounded in pithy expressions and in illustrative anecdote, although his gesture was ungraceful.
Up to this date Stanhope had remained on friendly terms with William Pitt, but differences over the French revolution led to their permanent estrangement (Stanhope, Pitt, ii. 180-1). He was chairman of the 'Revolution Society,' which was founded in 1788 to commemorate the centenary of the English revolution of 1688, and he forwarded to Paris the address of congratulation on the capture of the Bastille, which had been moved at its meeting on 4 Nov. 1789 by Dr. Price. To Rochefoucault he sent the resolution of congratulation on the establishment of liberty in France, which was proposed by Sheridan at a meeting held at the Crown and Anchor tavern in the Strand on 14 July 1790. It was read in the assembly on 21 July, and circulated in French. Letters sent by him to Condorcet were printed at Paris in 1791 and 1792, the first set arguing against the issue of false assignats, and the second relating to
