To mark Black History Month, Glasgow Anti-Racist Alliance has been running historical tours of Glasgow. These have been led by Stephen Mullen, a talented young historian from Strathclyde University who has studied the city's extensive involvement in the transatlantic slave trade. He is the author of an important book, to be published later this year, called It Wisnae Us. It challenges the Scots "myth of detachment", the commonly held belief that slavery was all the fault of the English and nothing whatsoever to do with the Scots.

The truth is otherwise. Even before the Act of Union with England, the Scots made attempts to get in on the profitable "triangular trade", but once in the union their involvement took off. Goods were taken to Africa by ship, exchanged for native peoples forcibly torn away from their families and communities and enslaved. These people were then shipped in hideous conditions to America and the Caribbean. There they were sold to be worked to death growing colonial crops such as sugar and tobacco, as "chattel" slaves, the property of their owners. The same ships returned to Scotland loaded up with plantation produce: the sweat of their labour.

The facts are shocking. The great mercantile wealth that Glasgow accumulated in the 18th century, so confidently expressed in the handsome buildings of the Merchant City, was based on the profits from slavery. Our Scottish banking system, so proudly defended by first minister Alex Salmond, grew as a direct result of the triangular trade. It gave us the first Scottish millionaires; "Virginia Dons" such as Andrew Buchanan, James Dunlop, James Wilson, Richard Oswald and John Glassford, who cornered the Chesapeake Bay tobacco trade. They have streets named after them to this day. Places such as Virginia Street, Jamaica Street, Kingston Bridge and Mount Vernon (named after a plantation in Virginia) underscore the Scots involvement in the Caribbean and America.

Part of the building that now houses the Gallery of Modern Art was built by merchant William Cunninghame as a lavish home, in no-expense-spared Palladian, plantation style from the profits gained from slavery. Richard Oswald, who lies buried with honours in Glasgow cathedral, founded a leading tobacco dynasty. His eponymous nephew bought Bance island off Sierra Leone, where he traded 13,000 enslaved Africans, a man so patriotic that he had slaves dressed in tartan as caddies on his island golf course.

Thirty-one slave ships sailed from Scottish ports between 1717 and 1766, 19 from Glasgow, the others from Leith, Montrose, Dumfries, Greenock and Port Glasgow. The huge warehouses that still line the shoreline in the latter ports were once filled with colonial crops produced through the enforced labour and suffering of enslaved Africans, profitably traded to the benefit of the Scottish economy.

By 1800, Scots ran 30% of the slave plantations in Jamaica. Nowadays the preponderance of Scottish surnames such as Campbell in Jamaica - indeed throughout the West Indies - reflects the practice of giving enslaved Africans the names of their Scottish masters. It's no coincidence that Shelly-Ann Fraser, Kerron Stewart and Veronica Campbell-Brown, Jamaica's Olympic sprinting medallists, all have Scottish names. Even Rabbie Burns's fine libertarian sentiments didn't prevent him buying a ticket in 1796 to sail to Jamaica to become, in his own words, "a negro driver". Slavery was then seen as a respectable way of making money for any ambitious, well-educated young man. Why doesn't everyone know about this ? Why isn't this history taught in Scottish schools?

We Scots have a selective view of our own history. We believe in our noble past, populated by romantic freedom fighters such as Bruce and Wallace. We habitually cast ourselves as valiant underdogs, driven by lofty ideals. Within this shortbread, Scots Wha Hae version of history, we are always the oppressed, never the oppressors.

When it comes to the sickening blot on the history of the world that is the transatlantic slave trade, most Scots are barely aware of any connection. This ignorance is the very reason why this subject should be made a core part of our history curriculum. Self-serving myopia has meant that there has been no systematic historical investigation of this skeleton in our nation's cupboard. Now the work of academics such as Stephen Mullen, Professor Tom Devine, Professor Geoff Palmer, Dr Eric Graham, Mark Duffill and the Reverend Dr Iain Whyte is addressing it.

The story isn't entirely shameful. Although Glasgow merchants were active proponents of slavery - when abolition was on the agenda they formed the Glasgow West India Association to strenuously oppose it - Glasgow was also a hotbed of anti-slavery sentiment, based on the strong moral critique advanced by academics at Glasgow University. A quarter of the citizenry of Glasgow signed an anti-slavery petition to parliament in 1826. Famous abolitionists, such as former slave Frederick Douglass and Harriet Beecher-Stowe, addressed packed audiences at the City Halls.

Good but mainly bad, this is part of our history, and all Scots should be aware of it.