King Charles has met 10 US presidents. Photos show their relationships through the years.

Charles was 10 when he met President Dwight Eisenhower at Balmoral Castle in Scotland during a laid-back visit in 1959.

The New York Times described the visit as informal, with the Queen driving Eisenhower around the estate and treating him to a picnic lunch on the shores of a lake.

He greeted President Richard Nixon at Buckingham Palace in 1969 during the president's first foreign trip in office.

Nixon met with Queen Elizabeth, Prince Philip, Charles, and Anne, who hosted a luncheon at the palace in his honor.

The following year, Charles visited the Nixons at the White House.

Nixon gave Charles and Anne a tour of the balcony of the South Portico.

Charles later revealed that Nixon tried to set him up with his daughter Tricia.

Charles and Tricia Nixon toured the Washington Monument and attended a baseball game together.

"That was quite amusing, I must say," Charles told CNN in 2021 of Nixon's matchmaking efforts.

He met President Jimmy Carter at the 1977 G7 Summit.

The third G7 Summit was attended by the leaders of Canada, France, Italy, West Germany, Japan, the UK, and the US.

President Ronald Reagan called Charles "a most likable person" after meeting with him at the White House in 1981.

Reagan wrote in his diary that White House ushers committed the faux pas of serving the prince tea from a tea bag instead of loose-leaf tea, according to The Ronald Reagan Presidential Foundation and Institute.

"It finally dawned on me that he was just holding the cup and then finally put it down on a table. I didn't know what to do," Reagan wrote.

Charles welcomed the Reagans to the UK during an official visit in 1982.

The Reagans became the first US presidential couple to stay at Windsor Castle, according to the National Archives, and they attended a black-tie dinner at the castle, as well.

The Reagans returned the favor in 1985 by hosting then-Prince Charles and Princess Diana at a White House state dinner.

Diana famously danced with John Travolta during the event.

Charles later wrote in a letter to Nancy Reagan: "Diana still hasn't got over dancing with John Travolta, Neil Diamond and Clint Eastwood in one evening, not to mention the President of the United States as well!"

Charles became particularly close with Nancy Reagan and they kept in touch through letters until her death in 2016.

In one letter to the first lady, Charles opened up about his doomed marriage to Diana.

"One day I will tell you the whole story," he wrote in a letter dated June 21, 1992, People magazine reported. "It is a kind of Greek tragedy and would certainly make a very good play!"

Charles attended Ronald Reagan's funeral in Washington, DC, in 2004.

Charles was accompanied by former British Prime Minister Margaret Thatcher and then-Prime Minister Tony Blair.

Charles first met George H.W. Bush while he was serving as Reagan's vice president.

Charles and Diana dined with then-Vice President George H.W. Bush and Barbara Bush at the British Ambassador's Residence in 1985.

They reunited in 1989 during Bush's own presidency.

Charles joined the Bushes for dinner at Camp David.

Charles and Bush continued to see each other at official events even after Bush was no longer president.

In 2002, both Bush and Charles attended a rededication ceremony for the American Air Museum of Great Britain in Cambridgeshire.

Charles attended George H.W. Bush's funeral in 2018 on Queen Elizabeth's behalf.

Charles, who was greeted by then-Vice President Mike Pence at the National Cathedral, was seated next to former British Prime Minister John Major during the service, Harper's Bazaar reported.

President Bill Clinton and Charles were both in attendance at Israeli Prime Minister Yitzhak Rabin's funeral after his assassination in 1995.

Charles and Clinton were seated in the front row alongside leaders from France, Germany, Egypt, and the Netherlands.

First lady Hillary Clinton represented the US at Diana's funeral in 1997.

Bill Clinton did not attend the service since it was not an official state funeral, CNN reported.

Charles also worked with Hillary Clinton in her role as secretary of state.

In 2009, Hillary Clinton attended a meeting with world leaders hosted by Charles at St James's Palace to address environmental issues and the global climate crisis before the G20 summit.

President George W. Bush attended banquets with Charles during his state visit to the UK in 2003.

The Bushes' visit marked the first time a US president was hosted by the royal family since the Reagans' trip in 1982.

They attended a state dinner at Buckingham Palace and hosted a banquet in return at Winfield House, the American ambassador's residence, to thank the royal family for their hospitality.

Two years later, the Bushes hosted Charles and Camilla for a state dinner at the White House.

The state dinner menu included buffalo tenderloin, a salad with Vermont camembert cheese and spiced walnuts, and petit fours cake for dessert, according to the George W. Bush Presidential Library and Museum.

In his remarks, Charles said that returning to the White House brought back "many fond and happy memories" of his first visit with Anne in 1970, "when the media were busy trying to marry me off to Tricia Nixon."

Charles first met President Barack Obama and Michelle Obama at a 2009 reception for G20 leaders at Buckingham Palace.

The G20 leaders discussed responses to the global financial and economic crisis.

Charles met with Obama at the White House in 2011 ahead of the president's first state visit to the UK.

During the US visit, which occurred shortly after Prince William and Kate Middleton's royal wedding, Obama congratulated Charles and joked that he wouldn't have been able to handle the pressure of such a large ceremony since his 1992 wedding to Michelle Obama had just 300 guests.

Charles spent more time with the Obamas during their UK state visit.

Charles and the Obamas met at Winfield House and attended a state dinner at Buckingham Palace.

At a commemorative D-Day ceremony in 2014, Obama appeared to salute Charles in his military uniform, eliciting a chuckle from the then-Prince of Wales.

The ceremony marked the 70th anniversary of D-Day.

During another White House visit in 2015, Obama was overheard telling Charles that Americans like the royal family "much better than their own politicians."

"I don't believe that," Charles was heard replying in footage captured by CBS News in the Oval Office.

Charles encountered President Donald Trump and first lady Melania Trump at social events in New York City long before they entered politics.

Charles was photographed chatting with the Trumps in 2005 at a reception hosted by the Museum of Modern Art.

As president, Trump remained skeptical about Charles' environmental causes.

In a June 2019 meeting at Clarence House during a state visit, the two leaders discussed the climate crisis, which Trump has been dubious of.

In 2018, Trump said he didn't believe his own administration's report about the economic impact of the climate crisis, and dismissed a question about human activity contributing to the climate crisis in 2022 by saying "the climate has always been changing."

Trump told ITV that his meeting with Charles was scheduled to last 15 minutes, but went on for an hour and a half.

Charles "did most of the talking," though Trump did say that he told the then-Prince of Wales that the US "has among the cleanest climates there are."

"He is really into climate change, and I think that's great. I totally listened to him," Trump told ITV.

Trump continued: "What he really wants, and what he really feels warmly about, is the future. He wants to make sure future generations have climate that is good climate, as opposed to a disaster. And I agree."

But in her memoir, "I'll Take Your Questions Now," former White House press secretary Stephanie Grisham wrote that, after the meeting, Trump had rolled his eyes and complained that their "terrible" conversation consisted of "nothing but climate change."

A Clarence House spokesperson told CNN that Trump and Charles had developed a "good working relationship" following another meeting in December 2019.

The Trumps stopped by Clarence House for another short visit while in the UK for a NATO summit.

President Joe Biden got to know Charles while serving as Obama's vice president.

Biden joined Charles and Camilla in the Oval Office during their 2015 visit to the US.

After Queen Elizabeth's death in 2022, Biden assured the new king that his late mother would "be with him every step of the way."

The Bidens paid their respects by visiting the Queen's coffin at Westminster Hall, signing the official condolence book at Lancaster House, and attending her state funeral.

"Our hearts go out to the royal family — King Charles and all the family," Biden told reporters. "It's a loss that leaves a giant hole. And sometimes you think you'll never overcome it. But as I've told the king, she's going to be with him every step of the way — every minute, every moment. And that's a reassuring notion."

In May 2023, Jill Biden attended Charles' coronation without her husband — no US president has ever attended one.

Trump blasted Biden as "very disrespectful" for skipping Charles' coronation, but US presidents have historically sent delegations and never attended the event themselves.

In July 2023, Biden met with Charles at Windsor Castle to discuss the climate crisis.

Biden and Charles met privately before holding a larger gathering with investors and philanthropists to discuss renewable energy and deforestation among other issues, the White House said in a statement.

Biden appeared to break royal etiquette rules by touching the king's arm and putting his hand on his back, but Charles returned the gesture.

Former royal butler Grant Harrold, who worked for Charles between 2004 and 2011, previously told Business Insider that touching a royal family member when they didn't initiate contact with a movement like a handshake is considered a breach of royal etiquette.

Charles didn't seem to mind — he was seen returning the gesture as the two leaders walked side by side.