BUCHANAN, Cochrane, Dennistoun, Dunlop, Glassford, Ingram, Oswald, Speirs. The list of Glasgow slavers, revered as “Tobacco Lords”, who are celebrated in the naming of the streets and districts of the city is as long as it is shameful.

Even in recent decades Glasgow City Council has thought it proper to renovate and promote “The Merchant City” without facing up to the central role of African slavery in its creation. Was a second thought given when this hub of music venues, theatres, clubs, bars and restaurants was relaunched under its existing name?

The Gallery of Modern Art in Glasgow’s Royal Exchange Square stands, we are often told, in premises formerly inhabited by the Royal Bank of Scotland. Less often are we reminded that, prior to its purchase by the bank, the grand building was the ostentatious mansion of the tobacco tycoon William Cunninghame, who reputedly owned more than 300 enslaved human beings on his plantations in Jamaica.

The denial and neglect of this history, even now, in the 21st century, sits uncomfortably with Glasgow’s renaming, in 1986, of St George’s Place as Nelson Mandela Place. Many Glaswegians are, justly, proud that Mandela was granted the freedom of our city, and that he, famously, came to Glasgow in 1993 to recognise our solidarity with the struggle against apartheid in South Africa.

However, as the National Theatre of Scotland’s latest work, Ghosts, by Glasgow-based theatre artist Adura Onashile, makes abundantly clear, Glasgow and Scotland have a considerable distance to go in facing up to their, that is our, racial history.

The piece is a promenade drama conducted through a smartphone app. One begins one’s journey outside the former Ramshorn Kirk in the Merchant City.

Standing outside the former church, you are beginning on Ingram Street. The thoroughfare is named after Archibald Ingram, former Lord Provost of Glasgow and, with his brother-in-law John Glassford, slave holder in numerous tobacco plantations in the North American colonies.

READ MORE: 'Augmented reality' artwork takes audience through Glasgow's slave-trading past

Activate the app on your phone and you hear a young African man (played powerfully by Reuben Joseph) speak the undeniable words: “I am this city. I am my master’s house. Built with my blood, my sweat, my dying.”

This unnamed young man will be your guide through the streets and history of Glasgow. At some point in the 18th century, he was torn from his mother as she was sold into slavery.

She is poked, prodded, evaluated with no more respect than a piece of livestock.

Most likely bound for the plantations of the Caribbean or North America, she will be transported in conditions worse than would have been afforded to cattle or sheep. She stands a 16% in transportation.

Her son will be transported to Scotland. He will seek solace in the memory of her song.

He will be dressed up like a doll, displayed as a curio, and worked as an enslaved servant in the grand house of a tobacco merchant. When he escapes, he will be hunted as missing “property”.

As we hear this terrible story, we see on our screen the titular “ghosts” of the piece’s title. Brought to us by way of AR (augmented reality) visuals, they represent the almost innumerable, certainly unnamed enslaved Africans whose unconscionable suffering created the wealth of Glasgow’s merchants.

Our journey takes us to Virginia Street (named, like Jamaica Street, after a location of the Glasgow merchants’ plantations). There, without irony, at the opening to Virginia Court, a bright blue plaque informs us that we are on the “merchant trail”.

THE young man’s story, his hiding, his running from the police, takes us to Cunninghame’s former mansion, now a gallery shuttered against the Covid pandemic.

It takes us along Buchanan Street (named for Andrew Buchanan, another Lord Provost of Glasgow and the proud owner of as many as 300 slaves in Virginia) and down to the River Clyde.

As it does so, the “ghosts” evoke the racial legacy of British imperialism, slavery and white supremacism. A legacy that brings us to the UK today, to black deaths at the hands of racist assailants.

Onashile’s writing combines poignantly with the acting, sound, music and visuals of the piece. The outcome is an art work that carries an intense resonance with the abominable history behind the locations.

One ends one’s journey through Ghosts at the railings on Clyde Street, with the statue of the Spanish anti-fascist fighter Dolores Ibárruri, aka La Pasionaria (symbol of a very different, proud Glasgow legacy), to one’s right. Turn around to face back to St Enoch Square.

There, on the wall in front of you, emblazoned in colourful defiance, are the words “Black Lives Matter”.

Ghosts runs from tomorrow until May 9. For more details visit nationaltheatrescotland.com