Noble and soldier. Educated at Winchester, Campbell inherited the estates and titles of Breadalbane on the death of his cousin in 1782. He was elected as a Fellow of the Royal Society in 1784 and served as a Scottish Representative Peer (1784 - 1806). In 1795, he was appointed a Lieutenant-Colonel of the Regiment of Fencibles which he had raised, rising to the rank of Lieutenant-General by 1814.
Campbell set about building the grand Taymouth Castle in 1806. He was created Earl of Ormelie and Marquis of Breadalbane in the British Peerage in 1831, the Earldom of Breadalbane having existed only in the Scottish Peerage.
He died at his home, Taymouth Castle.