1820 in Scotland

Incumbents

• Monarch – George III, George IV

  Law officers

• Lord Advocate – Sir William Rae, Bt
• Solicitor General for Scotland – James Wedderburn

  Judiciary

• Lord President of the Court of Session – Lord Granton
• Lord Justice General – The Duke of Montrose
• Lord Justice Clerk – Lord Boyle

  Events

• 13 March – Clan Grant raid on Elgin in a disputed election to the town council.
• 1–2 April – a proclamation, signed "By order of the Committee of Organisation for forming a Provisional Government", is distributed in the Glasgow area, beginning the "Radical War" in Scotland. The following day, around 60,000 – particularly weavers – stop work across a wide area of central Scotland.
• 5 April – Radical War: "Battle of Bonnymuir" – troops capture radicals near Bonnybridge.
• 8 April – Radical War: Radical prisoners from Paisley are freed from jail in Greenock after militia have killed eight of the crowd.
• 22 April – Walter Scott is created 1st baronet of Abbotsford in the County of Roxburgh in the Baronetage of the United Kingdom.
• 26 July – opening of Union Chain Bridge across the River Tweed between England and Scotland, designed by Captain Samuel Brown. Its span of 449 ft is the longest in the Western world at this time, and it is the first wrought iron vehicular suspension bridge of its type in Britain.
• 30 August – Radical War: Radical leader James Wilson, a Strathaven weaver, is executed for treason on Glasgow Green for his part in the rising.
• 8 September – Radical War: Radical leaders John Baird and Andrew Hardie are executed at Stirling for their part in the rising at Bonnybridge.
• 10 October – thief David Haggart murders the keeper of the Dumfries tolbooth while escaping imprisonment.
• 15 December – is wrecked near Craignish.
• 22 December–23 May 1821 – Radical War: Remaining prisoners are transported from England to Australia on the convict ship Speke.
• The United Secession Church is established as a Presbyterian denomination by union of various churches which have seceded from the established Church of Scotland.
• Finishing of work on Charlotte Square completes the first New Town, Edinburgh.
• Remainder of the Nor Loch in Edinburgh is drained to form what will become Princes Street Gardens.
• The Edinburgh botanical garden is moved to the Inverleith site of the modern-day Royal Botanic Garden Edinburgh.
• Inveraray Jail and Courthouse opened.
• The mineral thomsonite is first discovered, in Scotland.
• The Edinburgh Phrenological Society is established.
• John Walker sets up as a grocer and wine and spirits merchant in Kilmarnock, from where he will sell the blended Scotch whisky which will be branded as Johnnie Walker.
• The 6th Edition of the Encyclopædia Britannica is published.
• The Scottish Cemetery at Calcutta is established in British India.
• Approximate date
• * Construction of Ardlamont House.
• * Development of Barbaraville begins.
• * Gordon Setter dog breed standard formalised by Alexander Gordon, 4th Duke of Gordon.

  Births

• 4 April – David Kirkaldy, engineer, pioneer of materials testing
• 21 April – Peter Kerr, architect
• 1 May – Henry Yule, orientalist
• 24 May – William Bruce Robertson, Presbyterian preacher
• 29 June – Patrick Stirling, locomotive engineer
• 5 July – William John Macquorn Rankine, physicist
• 6 August – Donald Smith, 1st Baron Strathcona and Mount Royal, entrepreneur, statesman and philanthropist
• William Downie, gold prospector
• James Mckenzie, outlaw in New Zealand
• Edward Wilson, railway civil and locomotive engineer

  Deaths

• 14 January – Agnes Broun or Burnes, mother of Robert Burns
• 12 March – Sir Alexander Mackenzie, explorer of Canada
• 2 April – Thomas Brown, philosopher
• 15 April – John Bell, surgeon
• 4 September – John Dunlop, merchant and miscellaneous writer
• 6 September – James Ferguson, lawyer, politician and landowner
• 11 October – James Keir, geologist, chemist and industrialist
• 8 December – Archibald Colquhoun, lawyer and politician

  The arts

• Robert Chambers's publishing company publishes The Songs of Robert Burns.
• Walter Scott's novels The Abbot and The Monastery are published anonymously; also the first collected edition of his Poetical Works and his song "Hail to the Chief".
• Agnes C. Hall's novel The Highland Castle and the Lowland Cottage is published under the pen-name Rosalia St Clair.
• Robert Archibald Smith's The Scotish Minstrel: a selection from the vocal melodies of Scotland ancient and modern begins publication in Edinburgh.
• David Wilkie paints :File:Wilkie, David - Reading the Will - 1820.jpg|Reading the Will.