became chief minister, Lowther was appointed first lord of the treasury in the new administration, in which the tories slightly predominated, and was entrusted with the management of the House of Commons. In March 1690 he took a leading part in the important debate concerning the settlement of the revenue, demanding, but without success, the same terms that had been granted to James II; he obtained, however, a compromise, which was moderately satisfactory to all parties, with the probable exception of the king (Commons' Journals, 28 March 1690). He came in for a large share of the abuse which the whigs levelled at Caermarthen, whom he defended in the debate on 14 May, saying that if industry and ‘dexterity of management could expiate, he had done as much as man can do’ (Parl. Hist. v. 647). With Caermarthen, in fact, he agreed on political matters ‘as nearly as a very cunning statesman and a very honest country gentleman could be expected to do’ (Macaulay). On William's setting out for Ireland in June (1690), Lowther was accordingly one of the council of nine appointed to advise Mary (Ralph, Hist. ii. 225), but in the autumn session of parliament he was replaced by Lord Godolphin as first lord of the treasury, a post for which he had from the first been conspicuously unfitted, being scrupulous and unready, with a temper the reverse of callous. A squib at this time, deriding ‘the dull, insipid stream of his set speeches, made up of whipt cream,’ describes him as
Rich in words as he is poor in sense,
An empty piece of misplaced Eloquence,
With a soft voice and a mosstrooper's smile
The widgeon fain the commons would beguile.
(State Poems, ii. 211.)
He retained his post as lord commissioner of the treasury (Luttrell, ii. 129), but seems to have taken little part in the administration, and in December retired in disgust into the country. In April 1691 he gave an illustration of his hasty temper by accepting a challenge from a Newcastle custom-house officer named Brabant, whom he had dismissed. He was badly wounded in the duel that followed (ib. ii. 210). In July he was on the board which examined Dartmouth, and in October he was, in his own words, severely ‘baited’ in the house on account of the two lucrative places that he held in the treasury and the household. As a courtier and placeman, who was also regarded as a deserter from the country party, he was exposed to reproaches which he had not the adroitness to parry. On this occasion he completely lost his head, almost fainted on the floor of the house, and talked wildly about righting himself in another place (Commons' Journals, 3 Dec. 1691; Macaulay). The country gentlemen's exasperation against Lowther, who, in addition to his places, had just received a special douceur of two thousand guineas from the king, was not entirely without justification; but the situation was aggravated by the presence in the forefront of Lowther's tormentors, of his Westmoreland neighbour, the notoriously corruptible Sir Christopher Musgrave [q. v.] In 1692 he was succeeded by Sir Henry Capel at the treasury board, which he resigned very willingly, leaving his department in the same state of inefficiency, confusion, and insolvency in which he had found it (see Cal. State Papers, Treasury Prefaces). About the same time it was rumoured that he had been offered and had refused a peerage. In November 1692, when the tide was turning against his party, he bravely defended Nottingham, and in January 1693 he strenuously opposed the Triennial Bill, though he had thus to dissent from his old patron Caermarthen. The same month he resigned his vice-chamberlain's gold key, and for the next three years he took little part in politics.
He had in 1685 taken down old Lowther Hall and rebuilt it on a large scale. He now devoted himself to adorning the interior, and called in Verrio to paint the ceilings; he also laid out gardens with elaborate care, and ‘indulged his taste for rural elegance, improving the aspect of the whole country by those extensive plantations, which he nurtured with the tenderest care’ (Neale, Seats, 1822, vol. v.) He also rebuilt the rectory and church of Lowther (ib.) Lowther Hall was almost completely destroyed by fire in 1720.
In June 1694 he was succeeded as lord-lieutenant by the Earl of Carlisle, and in May 1696 he was created a peer as Baron Lowther and Viscount Lonsdale, taking his title from the small town of Kirby Lonsdale in Westmoreland (Magna Britannia, 1731, p. 21). In March 1699, at the earnest request of William, he accepted the appointment of lord privy seal. He joined with Wharton in leading the peers' resistance to the Resumption Bill of 1700, and in July of that year was appointed one of the lords justices to govern the kingdom during the king's absence, but he died on the 10th of the same month. He was buried in Lowther Church, where a monument was set up to his memory (Le Neve, Mon. Angl. ii. 3). An unsigned portrait is at Longleat.
Lowther was married on 3 Dec. 1674 in Westminster Abbey to Katherine (d. January 1712), daughter of Sir Henry Frederic Thynne,
