During the time Queen Elizabeth II was on the throne there were a staggering 14 American Presidents - and Her Majesty met all of them apart from just one. The late Monarch was beloved by the American people, with many praising her for bringing warmth to the 'special relationship' between the UK and the US.
Having a state visit to see the Queen was the pinnacle of many President's time in the Oval Office - and she also made six official trips to America along with a number of private trips in pursuit of her loveof horse racing and thoroughbreds in Kentucky. Her Majesty was even gracious enough to overlook a number of blunders made by Presidents, and sometimes their First Ladies, who struggled to follow royal protocol.
Harry S. Truman
The Queen's first meeting with a president came while she was still a Princess - travelling to Washington to dine with Harry Truman in 1951.
The meeting followed her first royal tour of the US and the Trumans laid out all the stops, welcoming her at the airport with a 21-gun salute.
The then princess and her husband, Philip, stayed with the Truman family at Blair House, where they had been living while the White House was being renovated.
The president was captivated by the 25-year-old, calling her a "fairy princess", while the young royal was suitably impressed too, telling an aide she enjoyed Truman's straightforward manner.
Truman's grandson, Clifton Truman Daniel, said: "I know that he was impressed by her. They got along well. She was England for 70-plus years."
Dwight D. Eisenhower
Five years into her reign, the Queen made her first state visit to the US as monarch and was received by Dwight D Eisenhower.
The pair developed a close friendship and two years later, in August 1959, Her Majesty returned the favour by inviting him and wife Mamie to Balmoral.
While their conversations behind closed doors remain a secret, it appears the president was very taken with the cream teas that were being dished out.
Writing to Eisenhower in 1960, the Queen penned a warm letter that included her personal recipe.
"Seeing a picture of you in today’s newspaper standing in front of a barbecue grilling quail, reminded me that I had never sent you the recipe of the drop scones which I promised you at Balmoral," she said.
"I now hasten to do so, and I do hope you will find them successful."
John F. Kennedy
John F Kennedy and his glamorous wife, Jackie, took the world by storm when he entered the White House in 1961, but dinner at Buckingham Palace that summer didn't go smoothly at first.
The Queen was reportedly reluctant to invite the First Lady's sister and brother-in-law because they were divorcees, but she eventually relented.
In scenes depicted in Netflix's The Crown, the Queen is said to have felt upstaged when she hosted the couple.
Kennedy presented the royal with a signed portrait of himself in a silver Tiffany's frame, with a message reading: "To Her Majesty Queen Elizabeth II, with appreciation and the highest esteem, John F. Kennedy."
However, Jackie felt awkward at the dinner, reportedly saying later: "I think the Queen resented me. Philip was nice, but nervous. One felt absolutely no relationship between them."
The Queen and Jackie's relationship thawed after the assassination of Kennedy in 1963, with the former creating a memorial and scholarship fund in his honour.
Lyndon B. Johnson
The only President that the Queen did not meet was Lyndon B. Johnson.
Johnson had the top job from 1963 to 1969 but didn't have a face to face encounter with Her Majesty, but they did correspond on numerous occasions.
According to LBJ Library, neither extended an invitation for the other to visit their countries - and details of his potentially planned trip for London were never finalized.
However, she did meet with LBJ's wife, First Lady 'Lady Bird' Johnson during a trip to Texas in 1991.
There is no confirmed reason as to why the Queen didn't meet Johnson - but it may just have been the case that the timings never worked out.
Richard Nixon
President Nixon had met the Queen even before he entered the Oval Office, showing her and Prince Philip around the White House in 1957.
There was an awkward moment when the then Vice President had to borrow a suit in "desperation" because he had forgotten to bring black tie.
Having persuaded another guest to lend their outfit and dine alone upstairs, Nixon told the Queen: "I'm afraid this isn't my suit."
The couple hosted him at Buckingham Palace more than a decade later in 1969, but according to BBC America, the leader took a particular interest in the love life of Prince Charles.
Historian Sally Bedell Smith revealed that Nixon tried to play matchmaker between the heir to the throne and his daughter, Tricia.
"More than three decades later when Charles and his new wife, Camilla, visited George W and Laura Bush at the White House, he joked that the Bushes had better not try to fix up their twin daughters with his sons William and Harry the way Nixon had worked to set him up with Tricia," she said.
Gerald Ford
Gerald Ford committed a rather forgivable faux pas when he joined the Queen for a dinner commemorating the bicentenary of the American Revolution against the British in 1776.
During the White House ball, he reportedly referred to the monarch as 'Your Majesty' instead of 'Her Majesty'.
The Fords suffered further embarrassment when their son, Jack, was spotted wearing jeans and a T-shirt.
The Queen at least appeared to see the funny side, telling the First Lady: "Don't worry, Betty, I have one of those at home, too."
He also messed up by escorting the Queen to the dance floor, not realising that the next song to play was 'The Lady is a Tramp'.
Jimmy Carter
During a visit to Buckingham Palace in 1977, Jimmy Carter broke royal protocol by kissing the Queen Mother on the lips.
Thankfully he didn't attempt the same thing with Her Majesty, but her mother was taken aback by the experience and reportedly snapped back: "Nobody has done that since my husband died."
Her husband was King George VI, who died in 1952, at which point her eldest daughter became Monarch.
The Queen Mother took a dislike to Carter, although it seems her managed to charm the rest of the Royal Family.
Writing about their encounter, she wrote: "I took a sharp step backwards – not quite far enough."
Ronald Reagan
Of her many presidential acquaintances, the Queen appeared to hold a special affection for Ronald Reagan, with the pair bonding over a love of horse riding.
In 1982, the Reagans became the first US family to stay as overnight guests at Windsor Castle - and he returned the favour by hosting her at his Californian ranch the following year.
The president couldn't hide his excitement about the visit, writing in his memoir: "The highlight of our stay there came when the Queen and I went horseback riding together and Nancy and Prince Philip took a horse-drawn carriage ride. I must admit, the Queen is quite an accomplished horsewoman.
He added: "I spent that evening with the Queen, sitting on a sofa in the large living room, talking about our children like old friends."
George H. Bush
A die-hard baseball fan, George H W Bush decided to quite literally pull out all the stops when the Queen visited America in 1991.
ThePpresident took Her Majesty and Prince Philip, a fellow sports lover, to Baltimore's Memorial Stadium, where the Orioles were playing the Oakland Athletics
The Queen, dressed in a red dress, black gloves and three strands of pearls, met the players in the dugout, which was decked out with bulletproof glass.
Told to act naturally, Oakland's Jose Canseco did just as he was asked - chewing gum while shaking hands with the royals.
"I've been playing baseball for 10 years, and I'm used to a normal atmosphere," said the Orioles' Cal Ripken Jr after welcoming the couple. "This is a lot different. There's a lot of excitement."
She became the first British monarch to address the US Congress, with Bush stating that she had been "freedom's friend for as long as we can remember".
Bill Clinton
To commemorate the 50th anniversary of D-Day, the Queen invited Bill and Hillary Clinton to stay overnight on the Royal Yacht Britannia.
The 1994 trip was one of multiple occasions the pair crossed paths and Clinton spoke warmly of Her Majesty in her memoirs - even suggesting she could be a politician.
"Her Majesty impressed me as someone who but for the circumstance of her birth, might have become a successful politician or diplomat," he wrote in his memoir.
"As it was, she had to be both, without quite seeming to be either."
He added: "She's a highly intelligent woman who knows a lot about the world... I always marvel when we meet at what a keen judge she is of human events. I think she's a very impressive person."
George W. Bush
George W Bush's public speaking gaffes were a long-running joke during his presidential term - and he saved a fine one for the Queen.
At the end of a US visit in 2007, the president stumbled over a line in his speech during a Washington dinner, where he suggested the Queen had helped celebrate the US bicentennial in 1776, rather than 1976.
Mortified by his mistake, he winked at the monarch, saying: "She gave me a look that only a mother could give a child."
Always one for a dry one-liner, the Queen later began her own speech by saying: "I wondered whether I should start this toast by saying, 'When I was here in 1776'."
A laughing Bush responded: "Your Majesty, I can't top that one."
Barack Obama
When Barack Obama made a state visit to Buckingham Palace in 2009, wife Michelle Obama broke royal protocol.
The First Lady caused a stir when she breached the 'no touching' rule to give Her Majesty a sweet hug - a gesture which royal commentators branded "extraordinary".
Michelle later explained that their feet were aching in their high heels, so she put her arm around the Queen in a touching moment.
Writing in her memoir, Michelle said: "Forget that she sometimes wore a diamond crown and that I'd flown to London on a presidential jet; we were two tired ladies oppressed by our shoes.
"I then did what's instinctive to me anytime I feel connected to a new person, which is to express my feelings outwardly. I laid a hand affectionately across her shoulder."
Michelle recalled that Her Majesty had commented on how tall she was and asked her if her shoes pinched, so they bonded over their shared pain.
She added: "I couldn't have known it in the moment, but I was committing what would be deemed an epic faux pas.
"If I hadn't done the proper thing at Buckingham Palace, I had at least done the human thing. I daresay the Queen was okay with it, too, because when I touched her, she only pulled closer, resting a gloved hand lightly on the small of my back."
Donald Trump
Donald Trump has often shared his love for Her Majesty, with his Scottish-born mother being a big fan, but it didn't stop him breaching royal protocal several times during his state visit to the UK back in 2018.
While at Windsor Castle, Trump decided to shake the Queen's hand rather than go for the traditonal bow, although it's not a hard and fast rule and he did appear to lower his head.
He also broke the rules when he walked in front of Her Majesty while they were inspecting her honor guard and even blocked her off when he abruptly stopped in her way.
Labour MP David Lammy tweeted: "What a disrespectful, discourteous, selfish and appalling way to treat a 92-year-old woman. Let alone the Queen of England, who has served this country faithfully for 66 years."
Trump had also appeared to keep the Monarch waiting for almost 15 minutes in the heat, with one of her aides spotted checking his watch, but he did actually arrived at the scheduled time.
The Apprentice star was invited back for a state dinner at Buckingham Palace the following year - and broke royal protocol once again while delivering his speech to the 170 guests in the ballroom.
He gestured towards Her Majesty and touched her back as she stood up for his toast, but royal protocol dictates that a person can only touch the Queen if she offers out her hand first.
But she seemed unfazed by the action as she toasted Trump's words - and clearly saw the funny side as she had a big grin on her face.
Joe Biden
President Joe Biden met the Queen for the first time in the 80s, but was reunited with her as the US leader during a state visit in June last year.
Mr Biden's motorcade swept into a G7 dinner reception after the Queen, which is considered to be a breach of royal protocol as all guests are traditionally meant to be in place before HM arrives for any official occasion.
The president said she had been "very gracious", adding: "I don’t think she'd be insulted, but she reminded me of my mother in terms of the look of her and just the generosity."
It seems like Biden, who attended Her Majesty's funeral last week, also broke an unspoken rule by revealing his personal conversations with the Queen.
He said they talked about a range of topics and the Queen asked him about his relationship with Xi Jinping and Vladimir Putin - the leaders of China and Russia.
The president told reporters: "She wanted to know what the two leaders that I - the one I'm about to meet with, Mr Putin, and she wanted to know about Xi Jinping."
It is very rare for anyone to disclose what is said during conversations with the Queen, although she may have given him approval.
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