The Most Honourable The Marquess of Breadalbane FRS
Portrait by Angelica Kauffman, 1770s
Born	John Campbell 30 March 1762 Kingdom of Great Britain
Died	29 March 1834(1834-03-29) (aged 71) Taymouth Castle, Perthshire, Great Britain and Ireland
Spouse(s)	Mary Gavin ​ (m. 1793)​
Issue	Mary Campbell John, Earl of Ormelie
Father	Colin Campbell
Mother	Elizabeth Campbell

Lieutenant-General John Campbell, 1st Marquess of Breadalbane FRS (30 March 1762 – 29 March 1834), known as John Campbell until 1782 and as The Earl of Breadalbane and Holland between 1782 and 1831, was a Scottish soldier and landowner.

Campbell was the son of Colin Campbell of Carwhin by Elizabeth Campbell, daughter of Archibald Campbell, of Stonefield. He was a great-grandson of Colin Campbell of Mochaster, younger son of Sir Robert Campbell, 3rd Baronet, of Glenorchy, and uncle of John Campbell, 1st Earl of Breadalbane and Holland. He was educated at Winchester.^[1]

In January, 1782, at age 19, Campbell succeeded his kinsman in the earldom of Breadalbane and Holland. This was a Scottish peerage and did not entitle him to an automatic seat in the House of Lords. However, in 1784 he was elected as one of the sixteen Scottish representative peer to sit in the House of Lords. The same year he was appointed a Fellow of the Royal Society.

Lord Breadalbane and Holland raised the Breadalbane Fencibles Regiment, in which he served as a lieutenant-colonel. He became colonel in 1802, a major-general in 1809 and a lieutenant-general in 1814. In 1806 he was created Baron Breadalbane, of Taymouth Castle in the County of Perth, in the Peerage of the United Kingdom, which entitled him to an automatic seat in the House of Lords.^[2] In 1831 he was further honoured when he was made Earl of Ormelie and Marquess of Breadalbane in the Peerage of the United Kingdom.^[3]

According to the book Braves and Buffalo Plains Indian Life in 1837, the Commander of a buffalo hunt presented seven captured buffalo to the Marquis of Breadalbane. The animals were shipped to the family estate at Taymouth, Scotland where they are said to have become tame and some young were born there. The expedition was recorded by watercolour artist Alfred J. Miller.

Lord Breadalbane married Mary Gavin, daughter of David Gavin, of Langton House, Berwickshire, in 1793. They had one son and two daughters. One daughter, Lady Mary Campbell, married Richard Temple-Grenville, 2nd Duke of Buckingham and Chandos.^[4] Their second daughter, Lady Elizabeth Maitland Campbell (1794–1878) married Sir John Pringle, 5th Baronet of Stichill, as his second wife.^[5]

He died at Taymouth Castle, Perthshire, in March 1834, aged 71, and was succeeded by his only son, John, Earl of Ormelie.^[6] The Marchioness of Breadalbane died in September 1845.^[1]

• Cokayne, G.E.; et al. (2000), The Complete Peerage of England, Scotland, Ireland, Great Britain and the United Kingdom, Extant, Extinct or Dormant, vol. II (new, reprint in 6 volumes ed.), Gloucester, U.K.: Alan Sutton Publishing, pp. 294, 296, 409

Michael Bell (1973) Braves and Buffalo, Plains Indian Life in 1837, Toronto,   University of Toronto Press, Public Archives of Canada, Watercolours of Alfred J. Miller, p 132.

• Hansard 1803–2005: contributions in Parliament by John Campbell, 1st Marquess of Breadalbane