James Stuart-Mackenzie

James Stuart-Mackenzie (30 October 1718 – 8 April 1800) was a Scottish politician and one of the founders of the Royal Society of Edinburgh in 1783. He was the second son of James Stuart, 2nd Earl of Bute, and Lady Anne Campbell, daughter of Archibald Campbell, 1st Duke of Argyll. His elder brother was John Stuart, 3rd Earl of Bute, who served as Prime Minister of Great Britain.

Born as James Stuart, he received education at Eton College, where he attended from 1728 to 1732. Following his studies in England, he traveled to Europe and attended the University of Leyden, graduating in 1737. Through his paternal grandmother Agnes Mackenzie, he inherited the Rosehaugh estates near Avoch in Ross-shire and subsequently adopted the additional surname Mackenzie.

Stuart-Mackenzie served as a Member of Parliament representing various Scottish constituencies. He was elected MP for Buteshire in 1747, serving until 1754. Later, he represented Ross-shire from 1761 to 1780. In 1761, he was sworn into the Privy Council of Great Britain. He was appointed Keeper of the Privy Seal of Scotland, serving from 1763 to 1765 and again from 1766 until his death in 1800.

Between 1758 and 1761, Stuart-Mackenzie was the British Minister at Turin. In 1761, he received the honor of Privy Counsellor. His involvement in Scotland’s political and administrative affairs was notable during this period.

In 1752, he sold the Rosehaugh estate and acquired ecclesiastical lands of Kirkhill in Meigle from Sir Thomas and William Nairn. On the site of the former castle used as a church grange, he built Belmont Castle, investing approximately £10,000 in its construction.

A keen scholar and astronomer, Stuart-Mackenzie was known for his interest in scientific pursuits. He was responsible for constructing an observatory on Kinpurnie Hill, part of his estate. The observatory was designed by Alexander Bryce, a minister from Kirknewton and East Calder, though it remained incomplete. A telescope believed to be specially made for him is housed in the Robert Whipple Collection at the University of Cambridge.

Stuart-Mackenzie was married in 1749 to Lady Elizabeth Campbell, his first cousin and daughter of John Campbell, 2nd Duke of Argyll. The marriage did not produce any surviving children. Lady Elizabeth died in July 1799, and he passed away less than a year later, on 6 April 1800.

Following his death, a legal decision in 1803 stipulated that his estates be passed to his nephew, James Stuart-Wortley-Mackenzie. He was related by marriage to Robert Bruce, Lord Kinnet.