The Queen, in her 70 years as head of state, saw an impressive 15 Prime Ministers, from Second World War statesman Sir Winston Churchill to the current PM, Liz Truss.
MORE: The Queen's remarkable life in pictures
News of Her Majesty's death has been met with an outpour of grief from political leaders from across the world. During her reign, former PMs have consistently paid tribute to the monarch for her sage advice and impressive knowledge of home and world affairs during their private weekly audiences.
WATCH: When have Prime Ministers had to apologise to the Queen
Take a look at the Queen's moments with the various Prime Ministers she has welcomed throughout her reign...
Sir Winston Churchill - 1951-55
Sir Winston, her first prime minister, was thought to be her favourite. He greeted the young, grieving monarch back on British soil after her sudden return from Kenya on the death of her father, King George VI.
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When Sir Winston retired in 1955, the Queen sent him a hand-written letter telling him how much she missed him and how no successor "will ever for me be able to hold the place of my first Prime Minister". Sir Winston had nurtured her through the early years, giving her invaluable advice.
Sir Anthony Eden - 1955-57
The Queen's relationship with the starchy Sir Anthony Eden was certainly more formal. The Tory leader was in power for less than two years – between April 1955 to January 1957.
Harold Macmillan - 1957-63
The former PM was an urbane figure in contrast to the monarch who is a countrywoman at heart. However, on one occasion, rather than discussing affairs of state at one of their audiences, the Queen and Mr Macmillan could be seen huddled over a transistor radio as US astronaut John Glenn was hurtling through space.
Sir Alec Douglas-Home - 1963-64
Sir Alec Douglas-Home reportedly met with royal approval. An aide said: "He was an old friend. They talked about dogs and shooting together. They were both Scottish landowners, the same sort of people, like old schoolfriends."
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Harold Wilson - 1964-70 and 1974-76
Harold Wilson endeared himself to the Queen. "They got on like a house on fire," one long-standing member of the Labour Party said. He used to join members of the royal family for riverside picnics at Balmoral.
Sir Edward Heath - 1970-74
Sir Edward Heath is said to have struggled with small talk and his weekly audiences with the Queen have been described as "frosty".
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James Callaghan - 1976-79
James Callaghan managed to establish a warm rapport. He said about the Queen: "One of the great things about her is that she always seems able to see the funny side of life. All the conversations were very enjoyable."
Baroness Margaret Thatcher - 1979-90
Things were very different with Margaret Thatcher, who reportedly found the traditional September weekend at Balmoral painful. Baroness Thatcher also could not abide the charades that she was expected to play after dinner at Balmoral and the Queen later, at a gathering of six of her premiers, joked about, "the party games which some of you have so nobly endured at Balmoral".
When Baroness Thatcher died in April 2013, the Queen took the unusual step of attending her ceremonial funeral – a personal decision and an indication of the Queen's respect for her first – and at the time her only – female prime minister.
Sir John Major - 1990-97
Sir John Major was popular with the royal family, and the Queen in particular, largely because of the genuine concern he expressed for the welfare of the two young princes William and Harry, first on the divorce of their parents and then on the death of their mother, Princess Diana.
Sir Tony Blair - 1997-2007
Sir Tony Blair was described in some palace quarters as a "head of state-in-waiting", and there were courtiers who were not happy with what they saw as his encouragement of a "people's monarchy". He had a long leadership of ten years - from May 1997 and June 2007.
Gordon Brown - 2007-2010
It's believed that Gordon Brown's relationship with the Queen was formal. The former Labour leader served from June 2007 and May 2010. Neither Gordon nor Tony were invited to the Duke and Duchess of Cambridge's wedding in 2011.
David Cameron - 2010-2016
David Cameron occupied Number 10 from May 2010 to July 2016. During his time as PM, he was forced to make a grovelling apology to the Queen in 2014 after his "purr-gate" blunder. Mr Cameron was caught on camera telling then New York mayor Michael Bloomberg that the monarch had "purred down the line" when he telephoned and told her the result of the Scottish independence referendum.
Theresa May - 2016-2019
Theresa May was the second female prime minister of the Queen's reign - taking up her post in July 2016 in the wake of the Brexit vote, more than a quarter of a century after Mrs Thatcher stood down. Ahead of the Platinum Jubilee, the former PM told the House of Commons: "She has seen prime ministers come and go, I was number 13." She added: "She has greeted us all with charm and consideration and with an impressive knowledge and understanding of the issues of the day." Her premiership ended in 2019 after she endured a torrid time dogged by the issue of Brexit. She was succeeded by Boris Johnson.
Boris Johnson - 2019-2022
Only a few hours into his post, Boris revealed what was said in his audience with the Queen as he accepted her invitation to form the next Government and become PM. A correspondent for Euronews NBC said the outspoken politician claimed the monarch quipped: "I don't know why anyone would want the job".
A few months into his premiership, Mr Johnson apologised to the Queen after the Supreme Court ruled his advice to her – imparted by Commons Leader Jacob Rees-Mogg at Balmoral – to prorogue Parliament for five weeks had been "unlawful".
Another apology to Buckingham Palace came from Downing Street amid the pandemic when two staff leaving events were held at Number 10 on April 16 2021, the eve of the Duke of Edinburgh’s funeral. Sue Gray’s report into the partygate scandal later revealed that staff carried on drinking at Number 10 the night before Philip's funeral until the early hours, with the last person not leaving until 4.20am.
On April 17 2021, the Queen sat alone in mourning for her late husband amid strict Covid restrictions, with the congregation limited to just 30 people. Mr Johnson revealed during a Parliamentary tribute to the Queen in her Jubilee year that his regular meetings with the monarch were always "immensely comforting, because she has seen the sweep of it".
Liz Truss - 2022-present
On 6 September, Her Majesty stepped back into the spotlight as she appointed Liz Truss as the new Prime Minister. Conservative leader Liz became the 15th prime minister of the Queen's seven-decade reign and the first who she has appointed in Scotland rather than London. In a statement, Buckingham Palace later confirmed: "The Queen received in audience The Right Honourable Elizabeth Truss MP today and requested her to form a new administration. Ms Truss accepted Her Majesty’s offer and kissed hands upon her appointment as Prime Minister and First Lord of the Treasury."
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