Lord Bute was born John Stuart into Scottish aristocracy in 1713. He was known as Lord Mount Stuart in his first ten years. He succeeded to the Earldom of Bute in 1723.  He attended Eton College, and then studied law at the Dutch universities of Groningen and Leiden. In 1737, he was elected a Scottish representative peer (Scottish peers electing 16 peers per Parliament, rather than being entitled to a seat in the House of Lords).

In 1751, Bute was appointed tutor to Prince George, the Prince of Wales. This would prove an important appointment as the two formed a close relationship, with Bute becoming one of George’s key advisers. Bute educated George on law, history, sciences, and arts, but also passed on a lot of his own political views. Bute was influenced by Lord Bolingbroke, who argued that the early Hanoverian monarchs had exercised insufficient control over politics, allowing a corrupt Whig oligarchy to take power, rather than using the royal prerogatives outlined in the Glorious Revolution of 1689. What was needed, Bute taught George was a Patriot King, who would use his powers, and act in the nation’s best interests.

When George became King George III in October 1760, he wanted Bute (who had continued as a Scottish representative peer) to play a role in politics. At this stage, Bute continued as an adviser, but his influence grew. The Newcastle-Pitt coalition was at the zenith of its power, but with British victory in (what history would later call) the Seven Years’ War now apparent, the ministry’s aims were becoming less clear, Pitt pushed for more conquests, but others wondered if it was time to rest on victory’s laurels.

In 1761, Bute was made Secretary of State for the Northern Department. When Pitt resigned in October 1761, Bute, who had been inserted into the Cabinet, became the dominant force in the waning Newcastle ministry. Newcastle finally resigned in May 1762, and George appointed Bute as Prime Minister.

Once in power, he concerned himself with the Peace at the end of the Seven Years’ War. The peace concluded the war in Britain’s favour, but Pitt was very critical.

Over 1762-63, Bute also conducted the ‘massacre of the Pelhamite innocents’ – dismissing large numbers of officials and office-holders appointed by Henry Pelham and the Duke of Newcastle. These figures included Newcastle, Rockingham, and the Duke of Grafton.

Bute’s major problem was that he had no political following. He was a royal appointee, and not someone with a natural set of allies in either the Commons or the House of Lords, though George Grenville and Henry Fox ensured some level of Parliamentary support. Until he became Prime Minister, he had never even spoken in the House of Lords.

His fellow politicians disliked him for being a royal sycophant, and the chauvinistic London mob disliked him for being Scottish. The radical MP John Wilkes was bitterly critical, and the newspaper The North Briton published ferocious attacks on Bute’s ministry. In November 1762, he was hissed and pelted by a mob on his way to Parliament, and he began to fear for his life. Bute asked the King if he could step down, but the King refused.  

In his budget in March 1763, Bute’s government introduced a tax on cider to help fund Britain’s war debts, but it proved deeply unpopular. Bute defended the measure in the Lords, but, once it had received royal approval, he was determined to resign. In April 1763, Bute resigned, suggesting George Grenville to replace him. Bute had been in office for just 317 days.

He continued to cast an influence over the King during the years that followed, but he was disappointed not to be included in government after Grenville fell in 1765. He wrote to the King to express his disappointment, after which the King effectively ended their acquaintance. After that, Bute pursued his passion of botany far more than politics (though his enemies incorrectly believed that he cast an influence over the King for decades further), and the plant genera Butea is named after him.

In 1736, Bute married Mary Wortley Montagu and they had eleven children.

He died in 1792 of injuries that he had received when he fell down a cliff whilst collecting plants a year and a half before.