[citation needed] He served in the Army from 1721 to 1747, and was aide-de-Camp to his uncle, John Dalrymple, 2nd Earl of Stair, at the Battle of Dettingen in 1743.

[1] His father was William Dalrymple of Glenmure and mother was Penelope Crichton, Countess of Dumfries.

[1] He married Lady Anne Gordon, daughter of William Gordon, 2nd Earl of Aberdeen and Lady Mary Leslie, on 2 April 1731; they had one son: He married Anne Duff, on 19 June 1762.

[1] At his death the titles separated, the Earldom of Dumfries passing to his nephew Patrick McDouall-Crichton, 6th Earl of Dumfries while the Earldom of Stair passed to his cousin John Dalrymple.

This biography of an earl in the Peerage of Scotland is a stub.