Dundas was instrumental in the encouragement of the Scottish Enlightenment,[2] in the prosecution of the war against France, and in the expansion of British influence in India.

At that time, the leaders of the abolitionist movement sought an immediate end to the slave trade, while the West Indian interests opposed any abolition at all.

Dundas was born in Edinburgh on 28 April 1742 in the house known as 'Bishop's Land' (a former lodging of the Archbishop of St Andrews) on the Royal Mile.

He became Solicitor General for Scotland in 1766; but after his appointment as Lord Advocate in 1775, he gradually relinquished his legal practice to devote his attention more exclusively to public affairs.

"[12] Dundas concluded his remarks by stating: "Human nature, my Lords, spurns at the thought of slavery among any part of our species."

[13] Michael Fry said that Dundas's success in Knight v Wedderburn was "instrumental in prohibiting not only negro slavery but also native serfdom in Scotland.

In 1778, Dundas made an attempt at proposing a Bill to relieve Scottish Catholics of their legal disabilities, but in response to severe riots in Edinburgh and Glasgow abandoned the project.

After holding subordinate offices under William Petty, 2nd Earl of Shelburne and Pitt, he entered the cabinet in 1791 as Secretary of State for the Home Department.

On 2 April 1792, abolitionist William Wilberforce sponsored a motion in the House of Commons "that the trade carried on by British subjects, for the purpose of obtaining slaves on the coast of Africa, ought to be abolished."

He argued, however, that a vote for immediate abolition would be ineffective, as it would drive the slave trade underground or into the hands of foreign nations, beyond Britain's control.

At that time he told the House that proceeding too quickly would cause West Indian merchants and landowners to continue the trade "in a different mode and other channels".

[21] He argued that "if the committee would give the time proposed, they might abolish the trade; but, on the contrary, if this opinion was not followed, their children yet unborn would not see the end of the traffic.

Abolitionists argued that West Indian assemblies would never support such measures, and that by making the abolition of the slave trade dependent on colonial reforms, Dundas was in effect indefinitely delaying it.

[32][33] Dundas was responsible for organising several British expeditions to the Caribbean to seize vulnerable French and Spanish possessions, the largest being that led by Sir Ralph Abercromy in 1795–6.

The governor of Jamaica, Alexander Lindsay, 6th Earl of Balcarres, used a contrived breach of treaty as a pretext to deport most of the Trelawny Town Maroons to Nova Scotia.

Walpole resigned his commission, and went back to England, where he became an MP and protested in vain in the House of Commons how Balcarres had behaved in a duplicitous and dishonest way with the Maroons.

The trial, in the House of Lords, attracted considerable notice because of "dislike of patronage and the Pittite 'system', anti-Scottish bias, and advocacy of financial and parliamentary reform".

She committed adultery (then known as "criminal conversation") with a Captain Everard Faukener in 1778, after 13 years of marriage, and abandoned Dundas and their four children, fleeing to an undisclosed location.

Henry Dundas became the owner of the family patrimony she brought to the marriage, in accordance with the law of the time, and raised their four children at Melville Castle near Edinburgh.

He attended debates in the House of Lords and maintained his position as a member of Privy Council, but kept a lower public profile.

[49] A monument to Dundas, modeled loosely on Trajan's Column in Rome, stands in the centre of St Andrew Square, Edinburgh.

"[50] It was designed in 1821 by William Burn, who was advised by Robert Stevenson after residents of the square expressed concern about the adequacy of the foundations to support a column of such height.

Furthermore, the Melville Monument, an obelisk erected in 1812 on Dunmore hill, overlooking the scenic village of Comrie in Perthshire, commemorates his life.

Historians of the slave trade and the abolitionist movement, including David Brion Davis, Roger Anstey, Robin Blackburn, and Stephen Tomkins commented that Dundas's actions delayed rather than facilitated abolition.

[57][58][59][60][61] According to Davis, "By making the abolition of the slave trade dependent on colonial reforms, Dundas suggested possibilities for indefinite delay.

Angela McCarthy notes that the revolutionary wars with France, and opposition in the House of Lords and in the royal family, presented enormous obstacles.

[65] In another Scottish Affairs article, McCarthy held that leading anti-Dundas activist Professor Emeritus Sir Geoff Palmer repeatedly misrepresented published sources.

By inserting the word "gradual" into the motion, Young says Dundas ensured a successful vote for the ultimate abolition of the trade in slaves.

A reference was made to Henry Dundas and his role in the abolition of the slave trade in the motion picture Amazing Grace (2006) where he was played by Bill Paterson.

[80] Dundas is also featured in Joseph Knight, by James Robertson (Fourth Estate, 2003) – a fictional account of the true story of the former slave for whom Dundas successfully appealed to two levels of Scottish courts, ultimately winning a declaration of Knight's emancipation, and the emancipation of all purported slaves on Scottish soil.