It has now been three hundred years since Sir Robert Walpole was appointed as Britain’s first Prime Minister in April 1721.

Walpole’s rise to power owes itself largely to the limited ability of King George I to speak English (he was German) and the king’s frequent absences from court and lack of interest in British public life. Although the term was informally used in Walpole’s time, it did not become an official title until the government of Sir Henry Campbell-Bannerman (1905-08). The Prime Minister is also known as First Lord of the Treasury. Boris Johnson became the 55th Prime Minister of Great Britain in 2019.

Walpole (1721-42) held the position for over twenty years, longer than anyone else. Margaret Thatcher was the seventh longest serving PM between 1979 and 1990, the longest record of anyone in the last hundred years. She was also the first woman Prime Minister of the UK. Theresa May (2016-19) was the second.

The youngest ever was William Pitt the Younger who was just 24 when he was appointed PM (1783-1801, 1804-06). No PM has been appointed who was under the age of forty since the 18th century, since Pitt the Younger, in fact, who was himself the only one ever appointed before he reached thirty. David Cameron (2010-16) was just 43 when he became PM and was the youngest person to hold the post since the 42-year-old Earl of Liverpool (1812-27).

Liverpool had succeeded Spencer Perceval (1809-12) who had the unfortunate distinction of becoming the only British Prime Minister to be assassinated. His assassin, John Bellingham, shot him in the lobby of the House of Commons in 1812. Bellingham had been a merchant who was seeking compensation after being imprisoned. He was hanged a week later. Five other Prime Ministers have died in office, all of natural causes and all before 1830.

The oldest ever British Prime Minister was William Gladstone (1868-74, 1880-85, 1886, 1892-94) who was eighty-four when he finally left office. Gladstone famously coined the phrase, “a young man in a hurry” to describe the young Winston Churchill, a man busy establishing himself as a soldier, journalist and as a potential statesman in the 1890s. Sixty years later, Churchill (1940-45, 1951-55) was in Gladstone’s position. He was eighty-one when he left Downing Street in 1955, the first PM of the present Queen’s reign.

In 2005, James Callaghan died one day before his 93rd birthday, making him the longest lived former Prime Minister there has ever been. Callaghan (1976-79) is unique in several respects. He is the only person ever to have held all four of the great offices of state (Chancellor of the Exchequer, Home Secretary, Foreign Secretary and PM). He was also married longer than any other PM: Audrey, his wife of 67 years, died just eleven days before he did. Callaghan is also often stated to have been the tallest British PM (he was 6ft 1in). Other sources say Lord Salisbury (1885-86, 1886-92, 1895-1902) was 6ft 4in and thus taller.

Lord Salisbury was Queen Victoria’s last Prime Minister and also the last to lead from the House of Lords. Lord Home became PM in 1963 quickly renouncing his peerage to do so, taking advantage of new laws made possible after a lengthy campaign by the former Viscount Stansgate. Stansgate had become Labour MP, Anthony Wedgwood Benn, later just Tony Benn. Home led for just one year as Alec Douglas-Home (1963-64).

Four Prime Ministers have been bachelors, most recently Edward Heath (1970-74) and nine have been widowers, most recently Ramsay MacDonald (1924, 1929-35). The Duke of Grafton (1768-70) is to date the only PM to have divorced and remarried while in office. This may change. Boris Johnson is separated from his wife, Marina Wheeler and engaged to be married to Carrie Symonds. They are the first couple not married to each other to live together in Downing Street.

Boris Johnson is also only the second British Prime Minister to be born outside the UK. Andrew Bonar Law (1922-23) was born in Canada. Boris Johnson was born in New York.