Records of prime ministers of the United Kingdom
The article lists the records of prime ministers of the United Kingdom since 1721. Period of service. The prime minister with the longest single term was Sir Robert Walpole, lasting 20 years and 315 days from 3 April 1721 until 11 February 1742. This is also longer than the accumulated terms of any other prime minister. The shortest period in office is more confused, depending on the criteria. The shortest ever period was only two days, a record held by Lord Bath, from 10 to 12 February 1746, who was asked to  form a government but was unable to find more than one person who would agree to serve in his cabinet. A satirist of the time wrote: "the minister to the astonishment of all wise men never transacted one rash thing; and, what is more marvellous, left as much money in the Treasury as he found in it." James Waldegrave, 2nd Earl Waldegrave was a prime minister for four days, from 8 to 12 June 1757. However, since neither of these Earls actually formed an effective government, there are other contenders for the record of shortest term of office among those  who actually governed the country. In November 1834, the Duke of Wellington declined to become Prime Minister in favour of Sir Robert Peel but formed a 'caretaker' administration for 25 days (17 November 18349 December 1834) while Peel returned from Europe. However, as a caretaker administration this might not necessarily be considered a term of office in its own right. Therefore, of those with clear and effective terms, the prime minister with the shortest single one was Lord Rockingham, whose second term lasted 96 days from 27 March 1782 until his death on 1 July 1782. However, combined with his  first term (13 July 176530 July 1766) his total time in office was 1 year and 113 days, which exceeds the total periods of several other prime ministers. (The Duke of Wellington had also served as Prime Minister between 1828 and 1830.) Consequently, the prime minister with the total shortest period in office was George Canning, whose sole term lasted 119 days from 12 April 1827 until his death on 8 August 1827. The prime minister with the longest period between the start of their first appointment and the end of their final term was the Duke of Portland, whose  first term began on 2 April 1783 and whose second and final term ended on 4 October 1809. Number of terms. A prime minister's "term" is traditionally regarded as the period between their appointment and resignation, dismissal (or death, in the case of those who die in office), with the number of general elections taking place in the intervening period making no difference. The only prime minister to serve four terms under that definition was William Ewart Gladstone (3 December 186820 February 1874, 23 April 188023 June 1885, 1 February 188625 July 1886 and 15 August 18925 March 1894 ). Terms of prime ministers and reigns of sovereigns. The office of Prime Minister has coincided with the reigns of eleven British monarchs (including a Regency during the incapacity of George III from 1811 to his death in 1820), to whom the prime minister has been constitutionally head of government to the sovereign's headship of state. Until 1837 the death of a sovereign led to Parliament being dissolved within six months which led to a general election. Results of such elections were: Served under most sovereigns. Stanley Baldwin is the only prime minister to have served three sovereigns, in succession  King George V, King Edward VIII and King George VI. Through being in office at transitions between reigns, eight prime ministers each served under two sovereigns: Number of prime ministers serving during reign. Elizabeth II has had 14 prime ministers serving during her reign (since 1952), from Sir Winston Churchill to the present prime minister, Boris Johnson. This ties a record previously set by George III, who had 14 prime ministers serving during his 59-year reign (reigned 1760–1820), beginning with the Duke of Newcastle. However, George III's last prime minister, Lord Liverpool, was appointed by his son (the  Prince Regent) during his father's final incapacity to rule. In downward numerical order, numbers of prime ministers in office during other reigns are: Prime ministers born during reigns in which they held office. Only seven prime ministers came to serve office under sovereigns in whose own reigns they were born. The present prime minister, Boris Johnson, is the fourth prime minister to have been born in the reign of the present sovereign Queen Elizabeth II. King George III (reigned 1760–1820) Queen Victoria (reigned 1837–1901) Queen Elizabeth II (acceded 1952) Cameron and Johnson have the additional distinction of being younger  than all of their monarch's children. <nowiki>*</nowiki> Perceval was assassinated in 1812. His is the only complete lifetime lived by a prime minister under a single sovereign. Prime ministers who lived under most reigns. Both Robert Walpole (1676–1745) and Lord Wilmington ( 1673–1743) lived under the reigns of the same six sovereigns: Charles II, James II, William III and his joint sovereign Mary II, Queen Anne, George I and George II. Sir Winston Churchill (1874–1965), Clement Attlee (1883–1967), Anthony Eden (1897–1977) and Harold Macmillan (1894–1986) all lived under the six reigns of Victoria, Edward VII, George V, Edward  VIII, George VI and Elizabeth II. Age. Age at appointment. The youngest prime minister to be appointed was William Pitt the Younger on 19 December 1783 at the age of 24 years, 6 months and 21 days. The oldest prime minister to be appointed for the first time was Lord Palmerston on 6 February 1855 at the age of 70 years, 3 months and 17 days. The oldest prime minister to be appointed overall, and oldest to win a General Election, was William Ewart Gladstone, who was born on 29 December 1809 and appointed for the final time on 15  August 1892 at the age of 82 years, 7 months and 3 days, following that year's General Election. Age on leaving office. The youngest prime minister to leave office was the Duke of Grafton, who retired in 1770, aged 34. The oldest was Gladstone, who was 84 at the time of his final retirement in 1894. Age differences of outgoing and incoming prime ministers. Greatest age difference – Lord Rosebery (born 7 May 1847) was 37 years 129 days younger than William Ewart Gladstone (born 29 December 1809) whom he succeeded after the final retirement of the latter in 1894 . Smallest age difference – George Canning (born 11 April 1770) was 67 days senior to Lord Liverpool (born 7 June 1770), whom he succeeded after Liverpool retired in 1827. Canning and Liverpool were one of four pairs of immediately consecutive prime ministers who shared a same birth year, the others being: The decade of the 1730s was the most productive for births of five future prime ministersLord Rockingham (born 1730, served 1765–66 and 1782), Lord North (born 1732, served 1770–82), the Duke of Grafton (born 1735, served 1768–70), Lord Shelburne (born 1737, served 1782–83) and the Duke of Portland (1738, served  1783 and 1807–09). Longest lived. The longest-lived prime minister was James Callaghan, Baron Callaghan of Cardiff, who was born on 27 March 1912 and died on 26 March 2005 at the age of 92 years 364 days, which was the day before his 93rd birthday. Prior to this the longest living prime minister was Harold Macmillan, 1st Earl of Stockton, who was born on 10 February 1894 and died on 29 December 1986 (aged 92 years, 322 days). Of the five former prime ministers currently alive, the oldest is John Major (born 29 March 1943), who is years old . If he reaches his 93rd birthday on , he will surpass Callaghan's record and become the longest-lived prime minister. Shortest lived. The shortest-lived prime minister was the Duke of Devonshire, who was born on 8 May 1720 and died on 2 October 1764 at the age of 44 years and 147 days. Longest lived after office. The prime minister who lived the longest after leaving office for the final time was the Duke of Grafton, who left office on 28 January 1770 and died on 14 March 1811, a total of 41 years and 45 days. The oldest  living former prime minister, John Major, left office on 2 May 1997. If he lives until 17 June 2038, by which point he will be 95 years and 80 days old, he will surpass Grafton's record. In recent years, the prime minister who lived the longest after leaving office was Edward Heath, whose term ended on 4 March 1974; he died on 17 July 2005, 31 years and 135 days later. Shortest lived after office. The prime minister who lived the shortest period after leaving office was Sir Henry Campbell-Bannerman, who resigned on 3 April 1908 and died  just 19 days later on 22 April 1908, while still resident in 10 Downing Street. Intervals between terms of office. The Duke of Portland was out of office between his two terms for 23 years and 101 days, from 19 December 1783 to 31 March 1807. The shortest interval (or "fastest comeback") was achieved by Henry Pelham, who resigned on 10 February 1746 but returned to office two days later (12 February) when Lord Bath had been invited to form a ministry but failed to do so. The shortest interval where an intervening ministry had been formed was achieved by  Lord Melbourne, who was out of office after being dismissed on 14 November 1834 but returned following the end of successor Sir Robert Peel's first ministry on 18 April 1835155 days (under six months) later. Female prime ministers. Female prime ministers have led the United Kingdom for a total of 14 years 219 days. Of all the prime ministers, only two have been female, both of whom were Conservative prime ministers: Birthplace. Two prime ministers were born in Ireland, both in Dublin in the Kingdom of Ireland before the Act of Union of 1801: Two further prime ministers were  born outside of the British Isles: All other prime ministers were born in Great Britain (47 in England and 7 in Scotland). Although of Welsh origin, David Lloyd George was born in Chorlton-on-Medlock, Lancashire. Facial hair. British male prime ministers when in office have been predominately clean shaven men, except for the following (as borne out by pictures): Bearded Moustached when in office In a pattern similar to the bald–hairy rule in Russia, between 1922 and 1957 men with moustaches succeeded clean-shaven men as Prime Minister, and vice versa. Side whiskers (sideburns) Nationality of prime ministers . The English are a majority within the United Kingdom. Several prime ministers have come from the other nations of the United Kingdom. Irish Scottish Welsh American Boris Johnson, first American-born prime minister (born in New York City). Also first British prime minister to have been potentially eligible for the office of President of the United States: until 2016 he was a natural-born citizen, but had not completed the required 14 years of US residence. He has both Muslim (Turkish and Circassian) and (Russian-Lithuanian) Jewish ancestry, one ancestor having been a Rabbi and a great grandfather having been  the journalist and politician Ali Kemal. Canadian Bonar Law, first Canadian-born prime minister (born in Kingston, Colony of New Brunswick, now Rexton, New Brunswick, Canada) Religious background of prime ministers. Britain's prime ministers have been predominately Church of England by denomination, in an office which has had input into the appointment of that Church's bishops. The first to hold the office from outside the Church of England was Lord Bute, who was a member of the Scottish Episcopal Church, while the Duke of Grafton was the first to convert away by formally becoming a Unitarian, after leaving  office. Prime ministers of other denominations (when in office, unless otherwise stated) were: Church of Scotland Scottish Episcopal Church Unitarian Church Congregationalist Church Baptist Free Church of Scotland Methodist Church Roman Catholic Church Judaism Irreligion Disabled prime ministers. At least seven prime ministers are known to have been physically disabled when in office: Others became disabled after leaving office, notably: Harold Wilson is believed to have been aware he had early-onset Alzheimer's disease when he resigned office in 1976, though he continued to serve as an MP until 1983. Prior to taking office, and while serving as an  MP, Alec Douglas-Home was immobilised following an operation to treat spinal tuberculosis from 1940 to 1943. General elections. Most prime ministers in office between general elections. There have been two intervals between general elections, both in the 18th century, when on both occasions five successive prime ministers were in office. In modern times, since members of the House of Lords ceased to hold prime ministerial office (after 1902), there were three prime ministers in office between the general elections of 1935 and 1945: Stanley Baldwin (retired 28 May 1937), Neville Chamberlain (resigned 10 May, and subsequently died 1940) and  Winston Churchill (until dissolution of the parliament). Most general elections contested as party leader. The most general elections contested by an individual is six. H. H. Asquith contested the January 1910, December 1910, 1918, 1922, 1923 and the 1924 general elections. The most general elections lost by an individual is five. Charles James Fox was unsuccessful after contesting the 1784, 1790, 1796, 1801 co-option and 1802 general elections, and subsequently never became Prime Minister. The most general elections won by an individual is four. Robert Walpole, Lord Liverpool, William Ewart Gladstone and Harold Wilson each won four general elections . Age at losing a general election. The youngest person to be on the losing side at a general election was Charles James Fox, who led his Whig Party to defeat in the 1784 general election when aged 35. The youngest prime minister to be on the losing side at a general election was Lord Rosebery, who, having resigned his ministry in May 1895, led his Liberal Party to defeat in the general election the following month when aged 48. Since peers ceased to hold this office (1902), the youngest losing prime minister was John Major, at 54 years and 33  days when the Conservative Party lost the 1997 general election. William Ewart Gladstone, was the oldest, at 76 years, when his party lost the 1886 general election, although he returned to office in 1892. The oldest prime minister to be defeated without returning to office was Benjamin Disraeli, 1st Earl of Beaconsfield, who was 75 when the Conservative Party lost the 1880 general election. Aged , Jeremy Corbyn is the oldest person to be on the losing side of a general election without ever becoming prime minister when the Labour Party lost the 2019 general election. Age at winning a general  election. The youngest prime minister to be on the winning side at a general election was William Pitt the Younger, who led his Tory Party to victory in the 1784 general election when aged 25. In recent years, the youngest prime minister to be on the winning side at a general election was David Cameron, who was 43 years and 209 days old when he led his Conservative Party to victory in the 2010 general election. William Ewart Gladstone, was the oldest. He was 82 years of age when he returned to office after his Liberal Party were successful in  the 1892 general election. The oldest prime minister to be victorious at a general election for the first time was Lord Palmerston, who was 72 years of age when his Whig Party won the 1857 general election. Prime ministers in office without a general election. Fourteen prime ministers never fought a general election while they held office (or to gain office), usually by serving terms sandwiched between the victor of one election and the prime minister who faced the next. Chronologically they were: Prime ministers who served from (or later entered) the House of Lords. John Russell was unique in  serving one entire term at Downing Street as Commons MP, when known as Lord John Russell (as younger son of a Duke of Bedford) in 1846–52, and his second and last entirely as a member of the Lords as the 1st Earl Russell in 1865–66, having been raised to the peerage between terms in 1861. Without counting Lord Russell, eighteen prime ministers served their entire terms from the House of Lords where they were already members, chronologically: <nowiki>*</nowiki> These five prime ministers never served in the House of Commons during their political careers. Three prime ministers were elevated  from the Commons to the House of Lords during their terms through being raised to the peerage: Lord North succeeded to his father's peerage as the 2nd Earl of Guilford in 1790 after being in office. Sir Alec Douglas-Home disclaimed his hereditary peerage as the 14th Earl of Home four days after coming to office in 1963 (under the Peerage Act of that year), giving up his seat in the Lords and subsequently sat in the Commons after succeeding in a by-election, pending which for 20 days he held office from neither House. He returned to the  Lords when made life peer as Baron Home of the Hirsel in 1974. Eleven prime ministers have served their entire terms as Members of the House of Commons but were elevated to the House of Lords afterwards by being created peers: In contrast 17 prime ministers preceding the current (Boris Johnson) have never become members of the House of Lords, including his five immediate predecessors. Henry Pelham (served 1743 to his death in 1754) was the first to be a lifelong 'Commoner' but the convention of prime ministers leading from the House of Commons only became established in the 20th  century. Holders of Irish peerages (with the exception of 28 Irish representative peers allowed after 1801, who were elected from among their peers) legally did not sit in the House of Lords in the Parliaments of Great Britain and the United Kingdom, but were allowed to sit in the House of Commons. Lord Palmerston was the only Irish peer to serve as Prime Minister, thus leading from the House of Commons. Service in House of Commons. The shortest period between entering Parliament and being appointed Prime Minister was achieved by William Pitt the Younger who became Prime Minister two years  after first becoming an MP. The longest period of service as an MP before becoming Prime Minister was 47 years for Lord Palmerston. The oldest debut of a future prime minister as MP was by Neville Chamberlain who was elected, aged 49 years 261 days, at general election in 1918. The youngest at first election was Lord Euston (later the Duke of Grafton), who was elected at by election on 10 December 1756 aged 21 years and 73 days. He also had the shortest period as an MP enjoyed by a prime minister, nearly five months, representing two successive seats  (the first of which he only held for 11 days before being elected for his second) until going to the House of Lords when he succeeded his father as the 3rd Duke of Grafton on 6 May 1757, eleven years before his term of office began. The longest service as MP was enjoyed by Sir Winston Churchill, who sat for a total of 63 years and 360 days, for five successive seats, between 1 October 1900 and retiring on 25 September 1964, excluding two intervals out of parliament (in 1908 and 1922–24), retiring as Father of the House. He was  in the Commons throughout both his terms as Prime Minister, and his service covered the terms of eleven other prime ministers, from Lord Salisbury (second ministry) to Sir Alec Douglas-Home, but did not serve under Bonar Law who was in office when Churchill was briefly out of parliament. David Lloyd George had the longest unbroken career as an MP, for one seat, Carnarvon Boroughs, from a by-election on 10 April 1890 until his death (having received a peerage on 1 January 1945 but not been able to take his seat in the Lords) on 26 March 1945a period  of 54 years and 350 days. From 1929 he had been Father of the House. It also covered the successive terms of eleven other prime ministers, from Lord Salisbury (first ministry) to Winston Churchill (first ministry). Of intervals between service in the Commons, Sir Alec Douglas-Home had the longest between automatically vacating his seat at Lanark on 11 July 1951 by succeeding his father and going to the House of Lords as the 14th Earl of Home, and gaining his next seat at Kinross and Western Perthshire in a by-election on 7 November 1963a total of 12 years  123 daysafter becoming Prime Minister and disclaiming his hereditary peerage. He had a previous interval out of the Commons between defeat in the 1945 General Election and returning in that of 1950 more than four years later. Of parliamentary constituencies that have been represented, none have been represented by more than one serving prime minister. Four future prime ministers sat for Newport, Isle of Wight (constituency abolished 1832): Lord Palmerston and Sir Arthur Wellesley (later the Duke of Wellington) in 1807–09, George Canning in 1826–27 and William Lamb, later Lord Melbourne in April–May 1827. It is rare for veteran  prime ministers sitting in the Commons to lose seats through electoral defeat at subsequent general elections. Those who have are: Prime ministers who were Father of the House. Five prime ministers through longest unbroken service became Father of the House. Sir Henry Campbell-Bannerman was the first prime minister to achieve this status, uniquely while in office, in 1907. He was still serving as an MP when he died shortly after retiring as Prime Minister. The others listed below became Father after the end of their terms. James Callaghan only 4 years and 36 days after end of office, while  at the other extreme Edward Heath became Father 18 years after the end of his. Education. School with most alumni prime ministersEton College20 (chronologically Sir Robert Walpole to Boris Johnson). Harrow School has educated 7 prime ministers, most recently Winston Churchill. University with most alumni prime ministersOxford University28 (Lord Wilmington to Boris Johnson). Its rival Cambridge University has educated 14 prime ministers, most recently Stanley Baldwin. University college with most alumni prime ministersChrist Church, Oxford13 (George Grenville to Sir Alec Douglas-Home) Vocational institution with most prime ministers as studentsThe Inns of Court11 (Lord Wilmington to Tony Blair). Of these , eight passed through Lincoln's Inn (William Pitt the Younger to Tony Blair). The first prime minister never to have been a university graduate was the Duke of Devonshire (served 1756–57); the most recent is John Major (served 1990–97). Armed forces veterans. The earliest prime minister to be an armed forces veteran was Henry Pelham (1743–54), who had served as a volunteer soldier in James Dormer's Regiment of Dragoons during the Jacobite rising of 1715 and fought at the Battle of Preston that year against the Jacobite forces. The most recent prime minister to be an armed forces veteran  was James Callaghan (1976–79), who served in the Royal Navy in the Second World War, from 1942 to 1945, seeing action with the East Indies Fleet and reaching the rank of Lieutenant. He was the only future prime minister to serve in the navy rather than the army. In contrast to many nations, Britain has had only two prime ministers who have been military generals: Lord Shelburne (1782–83), who was promoted from Lieutenant-General to full General in the British Army in the latter year, and the Duke of Wellington, who achieved the supreme rank of Field Marshal in 1813 . He was Prime Minister twice, in 1828–30 and 1834, in the interval between his two terms as Commander-in-Chief of the Forces. During his military career he took part in some 60 battles, seeing more wartime combat than any other future prime minister. No future prime ministers have yet served in the flying services, although Neville Chamberlain (1937–40), and Sir Winston Churchill (1940–45 and 1951–55), were honorary Air Commodores in the Auxiliary Air Force during their respective terms of office. Active service veterans. Jacobite Rising (1715) Jacobite Rising (1745) Seven Years' War French Revolutionary and Napoleonic Wars In addition , the following served in home based militia, volunteer or yeomanry units raised during the same wars but were not deployed abroad: Mahdist War Second Boer War First World War Second World War Although Eden and Alec Douglas-Home were Territorial Army officers at outbreak of war in 1939, neither was mobilised and the latter was invalided due to disabling spinal tuberculosis. War bereaved prime ministers. The following lost close relations in their lifetimes as a result of war: Also: Decorated. The most decorated British prime minister was Sir Winston Churchill, KG, OM, CH, TD, who received a total of 38  orders, decorations and medals, from the United Kingdom and thirteen other states (on continents of Europe, Africa, Asia and North America). Ten were awarded for active service as an Army officer in Cuba, India, Egypt, South Africa, the United Kingdom, France and Belgium. The greater number of awards were given in recognition of his service as a minister of the British government. Churchill was also the first and so far only British prime minister to receive a Nobel Prize (for Literature, in 1953). The most widely decorated prime minister by the number of states from which he received honours was  the Duke of Wellington, KG, GCB, GCH, who is known to have received 28 orders, decorations and medals from the United Kingdom and seventeen other states (all in Europe), in recognition of his military services. The British order of knighthood most frequently conferred on prime ministers has been the Order of the Garter, of which 30 male prime ministers (beginning with Sir Robert Walpole and later including Sir Winston Churchill and Sir Anthony Eden) have been Knight Companions (KG) and the first female, Margaret Thatcher, a Lady Companion (LG) of the Order. Nine prime ministers, including Thatcher, received it after  serving office. Currently, living Knight among them is John Major, knighted in 2005, and Tony Blair knighted in the 2021 New Years Honors. The first and so far only prime minister to have received a British gallantry award was Sir Anthony Eden who won the Military Cross (MC) while serving in the army in the First World War, before entering parliament. Number of living former prime ministers. None. After Sir Robert Walpole, three other prime ministers have been in office at a time when no former prime ministers were alive: One. After Lord Wilmington, eleven other prime ministers have been  in office at a time when only one former prime minister has been alive: Most. The most living former prime ministers at any one time has been five, which has happened several times: the first time was between January and November 1770 (while Lord North was in office) and Lord Bute, George Grenville, Lord Rockingham, Pitt the Elder and the Duke of Grafton were still alive (Grenville died in November 1770); from 1964 to 1965 (while Wilson was in office) with Clement Attlee, Sir Winston Churchill, Sir Anthony Eden, Harold Macmillan and Sir Alec Douglas-Home (Churchill died in January  1965); from April 1976 to January 1977 (while Callaghan was in office) with Sir Anthony Eden, Harold Macmillan, Sir Alec Douglas-Home, Harold Wilson and Edward Heath (Eden died in January 1977); from May 1979 to December 1986 (while Thatcher was in office) with Harold Macmillan, 1st Earl of Stockton; Alec Douglas-Home, Baron Home of the Hirsel; Sir Harold Wilson; Edward Heath; and James Callaghan (Macmillan died in December 1986); from November 1990 to May 1995 (while Major was in office) with Alec Douglas-Home, Baron Home of the Hirsel; Harold Wilson, Baron Wilson of Rievaulx; Edward Heath; James  Callaghan, Baron Callaghan of Cardiff; and Margaret Thatcher, Baroness of Kesteven (Wilson died in May 1995). There are currently five living former prime ministers, following the resignation of Theresa May in July 2019. The other four are John Major, Tony Blair, Gordon Brown and David Cameron. Living former prime ministers. There are currently five living former prime ministers. From oldest to youngest: The most recent death of a former prime minister was that of Baroness Thatcher (1979–1990) on 8 April 2013 (aged 87). Died in office. Seven prime ministers have died in office: Spencer Perceval is the only British prime  minister to have been assassinated. Lord Liverpool, Sir Robert Peel, Margaret Thatcher and John Major survived targeted assassination attempts in 1820, 1843, 1984 and 1991 respectively while in office, while Edward Heath survived one in 1974 after he had been ousted from office. Sir Henry Campbell-Bannerman and Bonar Law each resigned during their respective final illnesses. Law died five months after his resignation, but Campbell-Bannerman lived only another 19 days, dying at 10 Downing Street, the only prime minister ever to do so. Others who died within the same year they were Prime Minister were the Duke of  Portland who died in 1809, 26 days after he left office and Neville Chamberlain, who died in 1940, six months (less a day) after he left office, of a cancer that was undiagnosed at the time of his resignation. Died while immediate successor was in office. Eight prime ministers have died while their immediate successor was in office: All of the above-listed prime ministers were older than their immediate successors. The Duke of Portland and Lord Aberdeen are the only ones among this list who have both had immediate successors to die in office. Married. The longest-married prime  minister was James Callaghan who was married to his wife Audrey for 66 years from 28 July 1938 until her death on 15 March 2005. Four prime ministers married while in office, three to second wives: Widowed. Widowed the shortest. The British prime minister widowed the shortest is James Callaghan, who died on 26 March 2005. His wife, Audrey Callaghan, died on 15 March 2005, only 11 days before him. Divorced. Only three British prime ministers have been divorced: Bachelors. Only four British prime ministers have been bachelors: Kindred prime ministers. At least 24 British prime ministers were related to  at least one other prime minister by blood or marriage. Fathers and sons. Two sets of father and son have successively held the office: Brothers. The only brothers to hold the office were Henry Pelham (PM 1743–54) and his older brother and immediate successor Thomas Pelham-Holles, 1st Duke of Newcastle (PM 1754–56, 1757–62); both were Whigs. Full cousins. Pitt the Younger and Lord Grenville (who directly succeeded the latter in office) were the only set of full cousins to hold the office, their fathers being brothers-in-law. Boris Johnson and David Cameron are also, albeit more distant, cousins , through their common ancestor George II of Great Britain Uncles and nephews. There have been three blood uncle-nephew sets of prime ministers: Great-great-uncle and great-great-nephew. Lord Wilmington was two-greats uncle of Spencer Perceval, whose mother, Catherine (née Compton), Baroness Arden, was a blood great-niece of Wilmington. Father-in-law and son-in-law. The Duke of Portland, married in 1766 Lady Dorothy Cavendish, daughter of the Duke of Devonshire (who had died in 1764). Uncle-in-law and nephew-in-law. Sir Winston Churchill and Sir Anthony Eden. In 1952, during Churchill's  second term, Eden married Clarissa, daughter of John Strange Spencer-Churchill, Winston's brother, before succeeding to the office. Great-uncle-in-law and great-nephew-in-law. Lord Grenville was married from 1792 to Anne Pitt, daughter of Thomas Pitt, 1st Baron Camelford who was a nephew of William Pitt the Elder. Great-great-great-grandfather and great-great-great-grandson. Alec Douglas-Home was the great-great-great-grandson of Lord Grey. Great-great-great-uncle and great-great-great-nephew. Lord Russell and Alec Douglas-Home. Most children. The most prolific prime minister was apparently Lord Grey  who in wedlock fathered ten sons and six daughters. in addition to one illegitimate daughter by Georgiana Cavendish, Duchess of Devonshire who was subsequently raised by Grey's parents. Height. The tallest prime minister is believed to be Lord Salisbury, who was around in height, although Downing Street's own website lists James Callaghan as the tallest. The shortest prime ministers to take office were Margaret Thatcher, who was 5 feet 5 inches (1.65 m). and Lord John Russell who remained 'under' 5 feet 5 inches (1.65 m) throughout his adult life. Wealthiest. The richest prime minister was Lord Derby , with a personal fortune of over £7 million (about £444 million in today's money). The poorest was William Pitt the Younger, who was £40,000 (now over £1 million) in debt by 1800.