Britain's Queen Elizabeth II welcomed US President Joe Biden to Windsor Castle in June 2021.
It was her first one-on-one engagement with a world leader since the start of the Covid-19 pandemic. And it was one of her first public engagements after the death of her husband, Prince Philip.
During the Queen's 70-year reign, there were 14 US presidents. She met with all of them except for Lyndon B. Johnson.

Harry Truman: She wasn't Queen yet, but during a state visit to the United States in 1951, Elizabeth and her husband, Prince Philip, were received by former President Harry Truman and his wife, Bess. Truman is the only US President that Elizabeth met while she was a princess.
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Herbert Hoover: Hoover finished his tenure as President long before Elizabeth ascended to the throne. However, the opportunity for a meeting between the two arose in 1957 during the Queen's royal tour of the United States. Hoover is seated here to the Queen's right.
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Dwight D. Eisenhower: Eisenhower was the first serving President who Elizabeth met during her reign; he was also her host during her first state visit to the United States in 1957. They also met during a visit to Canada two years later in 1959. The Queen welcomed Eisenhower to the country before they formally opened the St. Lawrence Seaway with a short cruise aboard the royal yacht Britannia.
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John F. Kennedy: Amid much fanfare and huge media interest, Kennedy and his wife, Jackie, were dinner guests at Buckingham Palace in June 1961. He later wrote that he would "cherish the memory of that delightful evening," in a birthday letter written to the Queen. He added: "The people of the United States join with me in extending to your Majesty and to the people of the Commonwealth best wishes and hearty congratulations on the occasion of the celebration of your birthday. ... May I also at the same time say how grateful my wife and I are for the cordial hospitality offered to us by your Majesty and Prince Phillip during our visit to London last Monday. We shall always cherish the memory of that delightful evening."
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Richard Nixon: Nixon met Queen Elizabeth at Buckingham Palace shortly after becoming the 37th US President in 1969. The Queen prepared signed photographs of herself and Prince Philip as a small memento of the meeting. Nixon also brought a signed headshot. "I didn't bring my wife along this time, 'cause this trip was so hurried," he said. "But we just had a picture taken of the two of us. I would like to send you one of that because it would be much more pleasant to look at the two of us." Laughing, the Queen responded, "That's very nice of you."
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Gerald Ford: Ford and the Queen dance during a state dinner at the White House in 1976.
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Jimmy Carter: During a 1977 dinner at Buckingham Palace, Carter described the home of the British monarch as "one of the most beautiful places I've ever seen. And I think the whole royal family was there. ... I had a good place to sit -- I was between the Queen and Princess Margaret, and across the table was Prince Charles and Prince Philip and the Queen Mother." He continued: "One of the things I told Queen Elizabeth was how much the American people appreciated her coming over last year to celebrate our 200th birthday. And she said that it was one of the warmest welcomes she'd ever received."
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Ronald Reagan: The Reagans were the first US family to be the Queen's overnight guests at Windsor Castle in 1982. In his memoirs, "An American Life", the former President recalled his visit with the British royal family: "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. We will always remember our visit to Windsor Castle because of the Queen's and Prince Philip's warmth and welcoming hospitality -- they could not have been more gracious."
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George H.W. Bush: Bush visited the Queen at Buckingham Palace in 1989, and in May 1991, she was guest of honor at a state dinner in the White House. The pair exchanged toasts about the legacy of human rights and the rule of law bequeathed upon the United States by Great Britain. Meanwhile, the Queen spoke about her previous visits to the White House and the history of diplomatic relations between the two countries. Bush said during his welcome address: "We have got a lot of things in common. Americans share the Queen's love for horses. ... Most of all what links our countries is less a place than an idea. The idea that for nearly 400 years has been America's inheritance and England's bequest: the legacy of democracy, the rule of law and basic human rights."
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Bill Clinton: Clinton met the Queen more than once during his tenure. He said: "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. I like her very much." During a trip to Europe in 2000, Clinton said he noticed that although the Queen's hair had turned gray, she had what he described as "youthful eyes." He added: "She has these baby blue eyes, just piercing."
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George W. Bush: Bush visited Britain on an official state visit in 2003, and the Queen went to the United States in 2007 to celebrate the 400th anniversary of the founding of Jamestown. During his welcome speech, Bush fluffed his lines and said: ''You helped our nation celebrate its bicentennial in 17--. " Realizing his mistake of suggesting the then-81-year-old queen had been on the throne since the 18th century, Bush turned to the monarch and winked at her. Later Bush said she gave him "a look that only a mother could give a child." Here they are pictured in June 2004 watching a flyover in Arromanches, France. It was the 60th anniversary of the D-Day landings.
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Barack Obama: "There's one last thing that I should mention that I love about Great Britain, and that is the Queen," Obama said at the end of his joint press conference with British Prime Minister Gordon Brown during a visit to the UK in 2009. "And so I'm very much looking forward to meeting her for the first time later this evening. ... I think in the imagination of people throughout America, I think what the Queen stands for and her decency and her civility, what she represents, that's very important." Later, during a reception for G-20 leaders, Michelle Obama was seen to take the unusual step of putting her hand briefly on the back of the Queen. This was against protocol, but the monarch seemed to have reached out her hand first and didn't appear bothered by the first lady's gesture.
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Donald Trump: In 2019, the Queen hosted the Trumps for an official state visit that included dinner at Buckingham Palace. In a Fox News interview just after the trip to London, Trump called the Queen an "incredible lady" and said they had a lot of fun together. Some members of the British public and press were not amused, however, when Trump briefly walked in front of the Queen during a ceremonial inspection of the troops at Windsor Castle. The monarch had to do an awkward sidestep around him.
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Joe Biden: Biden first met the Queen as a young senator in 1982. He returned nearly 40 years later, after his first G7 summit as President. They held private talks inside Windsor Castle, and Biden later said he wished he could have spoken to her longer. "She was very generous," Biden said. He said he did not think she'd be insulted if he said she "reminded me of my mother in terms of the look of her and the generosity."
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