Japan's Princess Mako officially lost her royal status when she married her longtime partner, Kei Komuro, this week.
Now known as Mako Komuro, 30, the former member of the Japanese imperial family is the niece of Emperor Naruhito and daughter of Prince Fumihito, the Crown Prince of Japan.
The union, which has split public opinion, was delayed for more than three years because of a financial dispute involving her new mother-in-law. However, her father Prince Fumihito said of their marriage: "If that is what they really want, then I think that is something I need to respect as a parent."
Princess Mako also declined the 150 million yen ($1.35 million) she is entitled to on leaving the imperial family, palace officials said.
However, Princess Mako is certainly not the first royal to marry a commoner.
Here, we round up high-profile international royals who have married models, personal trainers, athletes, journalists and actors, and chart the controversy the courtships have provoked.
Sweden's Prince Carl Philip married Sofia Hellqvist
On June 13, 2015, Prince Carl Philip, the Duke of Varmland, 42, married Sofia Hellqvist, 36, a former glamour model and reality television contestant.
The pair met in 2009 at a nightclub in Bastad, southern Sweden.
Hellqvist was not immediately accepted by the Swedish public.
“From the beginning, there was a struggle for Sofia to be accepted,” says Margareta Gotthardsson, a Swedish royal reporter. “She has told the press that she and the prince tried to fall out of love with each other since they knew that it would be a struggle for them when her background was revealed.”
Carl Philip told Swedish TV that she was accepted by his sisters, Crown Princess Victoria, 37, and Princess Madeleine, 32, and parents, King Carl XVI Gustaf and Queen Silvia.
“My parents and my sisters were curious about her, open, and welcomed her with a big hug,” he said in 2015, adding she was “hung out to dry in a bullying type of way” by the press.
The couple are now parents to Prince Alexander, 5, Prince Gabriel, 4, and Prince Julian, 7 months.
Spain's King Felipe VI married Letizia Ortiz
Spain's then-Crown Prince Felipe, now aged 53, met journalist Letizia Ortiz Rocasolano, now 49, at a dinner party in 2002. Fast-forward 19 years, they are married, and known as King Felipe VI and Queen Letizia since the June 2014 abdication of King Juan Carlos I.
Not only was Queen Letizia a commoner, she was also a divorcee, a divisive detail in Catholic Spain. She was previously married to Alonso Guerrero Perez, a Spanish writer and a high school literature teacher, until 1999.
Felipe and Letizia announced their engagement on November 1, 2003, and went on to marry on May 22, 2004.
The 2015 book The Court of Felipe VI speculates that she wasn't immediately accepted by her in-laws. According to the book, by Daniel Forcada and Alberto Lardies, King Juan Carlos's friends referred to her as "the maid" and, at the time, he is said to have thought his son marrying a journalist was “the worst thing to happen” to the Spanish royals. The couple now have an approval rating of more than 60 per cent in Spain and are parents to Princess Leonor, 15, and Infanta Sofia, 14.
Monaco's Prince Albert II married Charlene Wittstock
Prince Albert II, 63, the Sovereign Prince of Monaco, head of the House of Grimaldi and son of Prince Rainier III and Grace Kelly, married South African swimmer Charlene Wittstock, 43, in 2011.
The pair met in 2000, during a swimming meet in Monaco, but didn't make their debut as a couple until the 2006 Winter Olympics in Turin, Italy.
Their engagement was announced by the palace in June 2010, with a wedding scheduled for July 8 and 9, 2011. However, it was moved to July 1 and 2 to accommodate a meeting with the International Olympic Committee.
The couple are now parents to twins, Princess Gabriella and Jacques, Hereditary Prince of Monaco, 6.
Britain's Prince Harry married Meghan Markle
One of the most high-profile royal weddings of the last decade has to be Prince Harry, 37, and Meghan Markle's. The British royal married American Suits actress Markle, 40, on May 19, 2018, six months after they announced their engagement, on November 27, 2017. Following their wedding, they became the Duke and Duchess of Sussex.
The couple have since stepped down as senior royals, announcing their plans to leave in January 2020.
They have spoken to Oprah Winfrey in a television interview about the duchess's experience as a member of the British royal family.
"In those months when I was pregnant, all around the same time ... So we have in tandem the conversation of, he won't be given security, he's not going to be given a title. And also, concerns and conversations about how dark his skin might be when he's born," Markle said, in the March interview.
"What? Who is having that conversation with you?" Winfrey asked. "There's a conversation with you ...? Hold up. There's a conversation?"
"There are several conversations ... with Harry," Meghan replied.
The couple now claim to be financially independent of the royals. In March, it was announced that Prince Harry has taken on a job at the Silicon Valley coaching and mental health firm BetterUp, a role that he hopes "creates impact in people's lives".
Denmark's Prince Frederik married Mary Donaldson
Frederik, Crown Prince of Denmark, 53, married Australian marketing consultant Mary Donaldson, 49, on May 14, 2004, after his mother, Queen Margrethe II, gave her permission in October 2003.
The couple met while Prince Frederik was in Australia for the Sydney Olympics in 2000.
They now have four children, Prince Christian, 16, Princess Isabella, 14, and twins, Prince Vincent and Princess Josephine, 10.
Prince Frederik is the heir to the Danish throne, the eldest son of Queen Margrethe II and Prince Henrik.
Norway's Crown Prince Haakon married Mette-Marit Tjessem Hoiby
On August 25, 2001, Norway's Crown Prince Haakon, 48, married single mother Mette-Marit Tjessem Hoiby, 48, with Denmark's Prince Frederik as his best man.
At the time, many Norwegians disapproved of their marriage, because Mette-Marit was a single mother, to a son born out of wedlock, and because of her participation in Oslo's rave scene during what she described as her “youth rebellion”.
Speaking following their engagement, she said: "Before, I used to love shopping, but now it's just stressful. Sure, buying clothes is fantastic for most girls, but not so great for me. What has effectively happened is that all of a sudden I need to have a good wardrobe for my new role in life. And I certainly didn't have many ball gowns before I met Haakon."
Prince Haakon is the heir to the Norwegian throne and the only son of King Harald V and Queen Sonja.
The couple have two children together, Princess Ingrid, 17, and Prince Sverre Magnus, 15, and Prince Haakon is stepfather to Marius Borg Hoiby, 24, Princess Mette-Marit's son from a previous relationship.
Netherland's King Willem-Alexander married Maxima Zorreguieta Cerruti
Then-Crown Prince Willem-Alexander, 54, met Argentinian marketing manager Maxima Zorreguieta Cerruti, 50, at the Seville Spring Fair in 1999. The couple have said that he did not introduce himself as a royal or a prince, but as Alexander. Maxima thought he was joking when he later told her he was the heir apparent to the Dutch throne.
Three years later, the couple married on February 2, 2002, and they became King Willem-Alexander and Queen Maxima following the abdication of Queen Beatrix in 2013.
Their relationship was not without controversy, primarily down to the role her father, Argentine politician Jorge Zorreguieta, had in the military dictatorship following the 1976 Argentine coup d'etat of General Jorge Rafael Videla. Zorreguieta claimed not to know about the deaths in the regime and before the couple's wedding, an inquiry into his involvement was conducted in the Netherlands. It was concluded that he was not directly involved with the atrocities but was "almost certainly aware of them". It was decided that Zorreguieta should not attend his daughter's wedding.
The couple now have three daughters, Princesses Catharina-Amalia, 17, Alexia, 16, and Ariane, 14.
Britain's Prince William married Kate Middleton
They are now best known as the Duke and Duchess of Cambridge, but Kate Middleton, 39, was not born to a British royal or aristocratic family.
The couple met at the University of St Andrews, where they were both studying, and after graduating in 2005, Middleton had a couple of part-time jobs, including a 12-month stint as an accessory buyer for high street brand Jigsaw. Her father, Michael Middleton, was a pilot for British Airways and runs Party Pieces with his wife, Carole Middleton.
Royal biographer Andrew Morton said of adjusting to royal life, "It's not like there's a school for princesses where you sit there and go through the procedures from A to Z. You learn it at the knee. You learn it from experience.
"Even Catherine Middleton, the point I'd make about her is that yes, she had the support of her family, and yes, she was British and knew what was expected, but nobody can prepare you for the level of intensity and the level of interest in you."
The couple married on April 29, 2011, and are now parents to Prince George, 8, Princess Charlotte, 6, and Prince Louis, 3. Prince William is second in line to the British throne after his father, Prince Charles.
Sweden's Crown Princess Victoria married Daniel Westling
Another Swedish royal to have married a commoner is Victoria, Crown Princess of Sweden, 44, who married Daniel Westling, 48.
A former personal trainer and gym owner, Westling gave up his business Balance Training in November 2009, but remained an equity partner.
Before they married, it was confirmed that Westling had moved into a one-bedroom apartment on the grounds of Drottningholm Palace in July 2008. The couple announced their engagement in February 2009 and went on to marry at Stockholm Cathedral on June 19, 2010.
As Princess Victoria is the heir apparent to the Swedish throne, Westling became Prince Daniel, Duke of Vastergotland, after their wedding. He took the surname of the Swedish royal family, Bernadotte, which makes his legal name Olof Daniel Westling Bernadotte.
The couple are parents to Princess Estelle, 9, and Prince Oscar, 5.