Family and Education

b. 15 Jan. 1744, o.s. of Kenneth Mackenzie.  m. (1) 7 Oct. 1765, Lady Caroline Stanhope (d. 9 Feb. 1767), da. of William, 2nd Earl of Harrington, 1da.; (2) Harriet Powell (formerly Lamb), da. of a London apothecary, s.p.  suc. fa. 18 Oct. 1761; cr. Visct. Fortrose [I] 18 Nov. 1766; Earl of Seaforth [I] 3 Dec. 1771.

Offices Held

Lt.-col. commandant 78 Ft. (the Seaforth Highlanders, which he raised) Dec. 1777- d.

Biography

Mackenzie spent much of his youth on the continent. James Boswell, who met him at the court of Brunswick in 1764, thought him ‘a lively pretty young man with the most perfect elegance of manners, having been abroad a great many years’.1 Soon afterwards Mackenzie returned to London; in 1765 married a first cousin of the Duke of Grafton; and in November 1766 obtained an Irish peerage. A man of fashion, belonging to a circle notorious for extravagance and profligacy, he seems to have had little concern for Scottish affairs. The Mackenzie clan, during the absence of their chief, had apparently accepted the leadership of James Stuart Mackenzie, whom Fortrose did not oppose in Ross-shire at the 1768 election. Instead, he was brought in for Caithness as a Government supporter, by arrangement with the Sinclair interest.

Fortrose’s attendance was poor; and his only known votes were for the naval captains’ petition, 9 Feb.1773 (marked in the King’s list as a ‘friend’), and with Government over the Middlesex election motion, 26 Apr. 1773. There is no record of his having spoken in the House. On Grafton’s rejoining the Government in 1771 Fortrose was created Earl of Seaforth in the Irish peerage; and at the end of the Parliament was listed by Robinson as a Government supporter.

Caithness was not represented in the 1774 Parliament; but Robinson mentioned Fortrose as a possible candidate for Tain Burghs, for Inverness-shire, and also for Ross,2 where, however, he apparently declined to stand against Stuart Mackenzie. Lord Adam Gordon, a Ross-shire voter, wrote to Sir Roderick Mackenzie of Scatwell, 29 Nov. 1773:3 ‘I wonder where your chief is to be brought in—or if he comes in at all? For my share I often wonder at his choice—and fancy he is the only man would prefer another’s to his own bottom.’ Seaforth himself showed little concern. In July 1774 he went abroad with his mistress Harriet Powell,4 whom he later secretly married.

In 1777 Seaforth offered to raise a Highland regiment; but recruiting was slow, and the King made difficulties over Seaforth’s nominations of officers; finally the regiment was embodied in May 1778. In 1779 Seaforth, because of vast debts, sold his estates to his second cousin and heir male, Thomas Mackenzie Humberston, and with them his interest in Ross-shire. He sailed with his regiment for India in June 1781 and died at sea, 27 Aug. 1781.

Ref Volumes: 1754-1790

Author: Edith Lady Haden-Guest

Notes

• 1. Private Pprs. iii. 15.
• 2. Laprade, 5.
• 3. Add. 39190, f. 197.
• 4. HMC Carlisle, 270.