MY instinct was to keep out of the controversy over Henry Dundas, the government minister who ruled Scotland in the late 18th century. He was the first Scot since the Union of 1707 to get to and stay at the top of UK politics.

After his death he was commemorated with a column and statue in St Andrew Square in Edinburgh. They were inscribed with platitudes, and a dispute is now going on whether they should also refer to his involvement with the slave trade. In fact, he was never much involved with the slave trade.

I can say this with some authority because I am Dundas’s biographer. Edinburgh University Press published my book on him and his family, The Dundas Despotism, in 1992. On the strength of that, I was invited three years ago to join the committee set up by Edinburgh City Council with the purpose of drafting a new inscription for the memorial.

I knew there would be conflict about it. I thought it better this should go on behind closed doors, where the committee would be able to thrash out the issues, rather than in the open amid appeals to public prejudice.

In the end, writing the detail of the inscription was delegated to me and another member of the committee who, however, never responded to my proposals except by giving excuses why he could not. I informed the council’s culture service, but this did not result in any progress either. I assumed the project was being quietly abandoned, because agreement to any single interpretation of Dundas’s versatile career was proving impossible.

Or at least that was what I assumed until last week, when I found out that instead the whole project had been taken over by others, without the original committee being informed of what was happening, let alone given an explanation. Now, the people in charge are council leader Adam McVey; an “academic at Edinburgh University” (not further identified); and Sir Geoffrey Palmer, former professor of brewing at Heriot-Watt University.

Of these the most significant is Palmer. Born in Jamaica, he arrived in the UK in 1955 and in 1989 became its first black professor. Recently, he has concentrated on human rights, on slavery and its functions in the British Empire.

In pursuing the topic, he read a book on the slave trade by a veteran historian, Hugh Thomas. Unfortunately even veteran historians sometimes make mistakes, and Thomas did so by accusing Dundas of having sabotaged the first parliamentary attempt to end the slave trade in 1792. He is supposed to have done so by inserting the word “gradual” into the planned timescale and in effect nullifying it.

Yet Dundas was a genuine opponent of the slave trade, and of other types of servitude. His early career as a lawyer demonstrated this. During the 18th century, Scots who had gone out into the empire to make their fortunes, and often to acquire slaves, began to bring them home again on their retiral to a country seat, perhaps, where they could live out the rest of their lives in peace and comfort.

One such slave was Joseph Knight who, on his master’s estate in Angus, fell in love with a local girl and wanted to marry her. Nobody could be sure if this was allowed, so Knight went to law in a case that eventually reached the Court of Session. Dundas was one of Knight’s counsel, presumably out of the goodness of his heart, for these were not proceedings likely to earn huge fees. Knight won his case and settled down as one of the first black Scots. James Robertson wrote an excellent novel based on this story.

One thing it builds on is that strong racial feelings were rare in the 18th century. William Dalrymple has written about this in his case study of The White Mughals. The Dundases had a share in what would become known as Anglo-Indian culture. A son of theirs, Richard, went to Calcutta and fathered a half-Bengali daughter.

WHEN he died, his parents had no qualms about sending for young Maria, bringing her back to Midlothian and planning her marriage to a local laird. She was a Dundas: being a dusky Dundas did not alter that.

Henry Dundas also got rid of the native type of slavery, or something very like it, which survived from an earlier Scotland. In his time, miners were still treated as serfs in a feudal system.

They were born into their station in life and could not legally change it. The same was true of their children. Early newspapers might carry small ads asking for escaped miners to be returned to their pits. Dundas thought this law unworthy of a civilised country. By two Acts of Parliament, 1775 and 1800, he abolished it.

With these credentials, it might be hard to understand why Dundas opposed the end of the slave trade, as he stands today accused of doing. In fact, this was not his position. He acted in his capacity as a parliamentary manager, doing what he could to fulfil the aims of his Prime Minister, William Pitt the Younger, the most senior politician opposed to slavery.

READ MORE: Henry Dundas: The Scotsman who kept slavery going

Dundas was this government’s Mr Fixit. Most ministers sat, in an aristocratic age, in the House of Lords. Pitt himself, in rank a commoner, came of a family blue-blooded with the best of them, the younger son of a former Prime Minister, the Earl of Chatham.

Dundas had a different kind of background, not among a landed but among a professional elite that relied for its political position on its competence in the service of the country. Jovial but ruthless, he had a useful knack of getting things done and dusted before anybody knew what he was up to.

In fact, he was the sort of practical politician that every good government needs. It was fine being a great and inspiring war leader, as Pitt learned to be. It was fine being a peerless idealist, like their contemporary William Wilberforce, the man who created the anti-slavery movement in the UK.

But it is absurd to believe

that only participants of the purest moral integrity can successfully practise politics. Almost the opposite is true. Politics, in fact, belongs to men ready for hard graft and dirty work. Without them, little would ever get done.

So Dundas went down to the City of London and talked to the financiers who had huge investments in the sugar plantations of the West Indies, at the time the most lucrative part of the Empire. He looked round the House of Commons and saw how many MPs were supported by these financiers.

Weighing it all up, he inserted the word “gradual” into Pitt’s planned legislation for abolition of the slave trade, hoping to win over those with doubts. And for this scheme of things he did indeed manage to persuade a majority of MPs to vote.

Even so, it was not enough. At this time the UK had a mixed constitution. Not yet a democracy, it gave roughly equal status to Crown (the government), Commons and Lords. In the Lords, the legislation was thrown out.

The disappointed Dundas judged further exertions to be a waste of his time, unless he had clear indications the parliamentary majority had shifted. In fact this did not happen till 1807, by which time his political career was over.

The UK was still the first country to abolish the slave trade. France had tried in 1792, but the despot Napoleon reversed the move. For humanitarian reform, it now proved, parliamentary process was more secure than revolutionary fervour. Dundas had done a good job.