He represented Richmond and Stirling in the House of Commons and also served as Lord Lieutenant of Orkney and Shetland.

In 1794 he was created Baron Dundas, of Aske in the North Riding of the County of York, in the Peerage of Great Britain.

[3] Lord Dundas notably purchased the right to the earldom of Orkney and lordship of Zetland from James Douglas, 14th Earl of Morton.

His son, the second Baron, was a Member of Parliament for Richmond and also served as Lord Lieutenant of Orkney and Shetland.

At first a Liberal, he held minor office in the second administration of William Ewart Gladstone but later joined the Conservative Party and served from 1889 to 1892 as Lord Lieutenant of Ireland.