A close relative of the Clan Campbell (his mother was a daughter of the 1st Duke of Argyll), Bute succeeded to the Earldom of Bute (named after the Isle of Bute) upon the death of his father in 1723. He was brought up thereafter by his maternal uncles, the 2nd Duke of Argyll and Archibald Campbell, 3rd Duke of Argyll, 1st and only Earl of Ilay. In August 1735, he eloped with Mary Wortley Montagu, whose parents Sir Edward and Lady Mary Wortley Montagu were slow to consent to the marriage. In 1737, he was elected a Scottish representative peer; despite being in London in December of that year, he did not participate in deliberations in the House of Lords. Because of his support for Argyll against Walpole, he was not re-elected in 1741. For the next several years he retired to his estates in Scotland to manage his affairs and indulge his interest in botany.