U.S. President Barack Obama looks on as Britain's Queen Elizabeth II signs a guest book after a reciprocal dinner at the Winfield House in London, on May 25, 2011. Obama and his wife Michelle enjoyed a regal welcome from Queen Elizabeth II, who has met every U.S. president but one since the 1950s. Obama's visit, the second stop on a European tour, comes as Britain seeks to prove its staying power despite fading military might and Washington looks to retool its decades-old alliance with Europe as a catalyst for global action.
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U.S. President George W. Bush welcomed to the United Kingdom by Queen Elizabeth II and Prime Minister Tony Blair, Nov. 19, 2003, amid tight security at Buckingham Palace. Traditional British pomp and ceremony, including a 41-gun salute, was laid on for start of the historic state visit. The president and Mrs. Bush stayed overnight at the Palace before the official welcome ceremony.
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U.S. President Bill Clinton, Britain's Queen Elizabeth II, First Lady Hillary Rodham Clinton, left, and daughter Chelsea, right, stand for photographers outside Buckingham Palace in London, Dec. 14, 2000. Clinton met with the queen on the final day of his three-day visit to Ireland, Northern Ireland and England.
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U.S. President George Bush and Queen Elizabeth II shake hands with Mike Gallego, Rick Honeycutt, and Jose Canseco of the Oakland Athletics at game between the Athletics and the Baltimore Orioles in 1991.
Queen Elizabeth II presents President Ronald Reagan with an honorary knighthood, June 14, 1989, at Buckingham Palace in London. Reagan was the first U.S. president in more than 35 years to be knighted by the queen. Only Republican presidents have received this honor. Looking on are Prince Phillip and First Lady Nancy Reagan.
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The queen riding with President Ronald Reagan on the grounds of Windsor Castle during his state visit on June 8, 1982.
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When President Jimmy Carter met Queen Elizabeth II in London's Buckingham Palace on May 1, 1977 he declined to bow and instead went for a kiss. The queen was said to have held a grudge against Carter over the hello smooch for years.
President Gerald Ford not only met Queen Elizabeth but took her for a spin around the dance floor when she visited the White House in 1976. Just as the two hit the dance floor, as shown here, the Marine band struck up "The Lady is a Tramp." The dance came during a state dinner honoring the queen and Prince Philip at the White House, July 17, 1976, in Washington.
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Queen Elizabeth II and British Prime Minister Edward Heath join President Richard Nixon and First Lady Patricia at Chequers, Heath's official country residence, Oct. 3, 1970. President Nixon made at least two trips to Britain during his presidency. Nixon's predecessor, Lyndon Johnson, was the only sitting U.S. president that did not meet the queen during her 60-year reign.
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Queen Elizabeth II and U.S. President John Kennedy on Jun 5, 1961, as they pose at Buckingham Palace in London. The Kennedy,s were dinner guests of the Queen.
Queen Elizabeth met former President Herbert Hoover in 1957, more than 20 years after he left the White House. She joined Hoover, left, and New York Mayor Robert Wagner at a luncheon in the Waldorf-Astoria hotel, New York, Oct. 21, 1957. The Mayor's luncheon was held in honor of the Queen after she was given a ticker tape parade up lower Broadway and an official city welcome at city hall.
Britain's Queen Elizabeth II stands in the grounds of Balmoral Castle, Scotland, with U.S. President Eisenhower, Aug. 29, 1959. From left to right, Prince Philip, Princess Anne, President Eisenhower, Queen Elizabeth II and Prince Charles.
President Harry S. Truman and Britain's Princess Elizabeth are shown as their motorcade got underway following the reception ceremony at Washington National Airport today. The Chief Executive welcomed Elizabeth and her husband, Prince Philip, Duke of Edinburgh, with the warm hope that "when you leave you will like us even better than when you came."