In three weeks’ time, royalty from across Europe and the UK will descend on Stockholm for what is expected to be the biggest gathering of kings and queens, and heads of state, in years.

Large celebrations will be held to celebrate the 80th birthday of Sweden’s King Carl VXI Gustaf, who is Europe’s longest reigning monarch, on April 30.

The guest list is expected to include a who’s who’s list of royals, stretching from Europe to the UK and even as far as Asia.

King Carl XVI Gustaf of Sweden and Queen Silvia, in a gala portrait released ahead of the King's 80th birthday on April 30, 2026, and the couple's 50th wedding anniversary on June 19, 2026.Sweden’s King Carl XVI Gustaf and Queen Silvia will be celebrated at two major events in the coming weeks. (Elisabeth Toll/The Royal House of Sweden)

Overnight, the Danish Royal House confirmed King Frederik X and Queen Mary will travel to Sweden for the historic occasion.

They will be joined by Queen Margrethe II and her younger sister Princess Benedikte. Queen Margrethe and King Carl are cousins.

The royal families of Sweden and Denmark, and Norway, have long been linked historically due to the Kalmar Union when the kingdoms of the three Scandinavian countries were brought together under a single monarch from 1397 until 1523.

It’s unclear whether Norway’s future queen, Crown Princess Mette-Marit, will be included in the festivities after recent revelations about her past relationship with Jeffrey Epstein.

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Sweden's royal family at the 2025 Nobel Prize awards, December 10. L-R: Christopher O'Neill, Princess Madeleine, Queen Silvia, King Carl XVI Gustaf, Crown Princess Victoria, Prince Daniel and Prince Carl Philip.Sweden’s royal family will welcome royalty from across Europe for the King’s 80th birthday celebrations. (Sara Friberg/The Royal House of Sweden)

Crown Princess Mette-Marit and her husband Crown Prince Haakon would usually be high on the list of invitees but the Royal House of Norway has yet to confirm if they will attend the gala event.

Mette-Marit has also taken a lengthy break from public life due to her chronic lung condition and the criminal trial of her eldest son, Marius Borg Høiby.

Norway’s King Harald V, 89, who has been invited along with his wife Queen Sonja, has had his own fair share of health issues in recent years and in February, he was hospitalised after contracting an infection while on holiday in Spain.

STOCKHOLM, SWEDEN - APRIL 30: Princess Madeleine, Princess Leonore, Christopher O'Neill, Prince Oscar, Crown Princess Victoria, Prince Nicolas, Princess Estelle, King Carl XVI Gustaf, Queen Silvia, Princess Sofia, Prince Gabriel, Prince Julian, and Prince Carl Philip of Sweden attend the King's birthday celebrations at the inner courtyard of the Royal Palace on April 30, 2025 in Stockholm, Sweden. (Photo by Michael Campanella/Getty Images)Last year Sweden’s newest royal, Princess Ines, made her palace balcony debut for the King’s 79th birthday. (Getty)

Other royals likely to attend the birthday celebrations are King Willem-Alexander and Queen Maxima of the Netherlands and King Philippe and Queen Mathilde of Belgium.

Spain’s head of state, King Felipe V and his wife Queen Letizia, could also be included, as could Monaco’s Prince Albert II and Princess Charlene, and Japan’s Emperor Naruhito and Empress Masako.

King Charles and Queen Camilla, of the UK, will not be in Sweden for the king’s 80th birthday as they will be in the US for a state visit. The Prince and Princess of Wales could attend instead, or the Duke and Duchess of Edinburgh may step in. The late Queen Elizabeth II and King Carl XVI Gustaf were third cousins, related through Queen Victoria.

Queen Mary of Denmark, pictured at the King’s 70th birthday in 2016, will attend the events later this month with King Frederik. (UK Press via Getty Images)

The last time Sweden hosted such a large gathering of visiting royals was for the King’s 70th birthday in 2016.

This time, the Royal House has a full day of events to celebrate the country’s longest-serving monarch.

The festivities will begin with a service of thanksgiving, known as a ‘Te Deum’, at the Royal Palace Church.

Sweden’s Armed Forces will then hold a military parade in the courtyard of the Royal Palace and members of the public will have the opportunity to see the king and his family.

A gala dinner will take place inside the palace and guests will wear their finest outfits, royal orders and military uniform, including tiaras for the females.

King Carl XVI Gustaf is the head of the Bernadotte family, a dynasty that has ruled Sweden for more than 200 years.

Norway’s King Harald and Queen Sonja are likely to attend, along with Belgium’s King Philippe and Queen Mathilde, but Crown Prince Haakon and Crown Princess Mette-Marit might avoid the celebrations. (AP)

His family will be in attendance including Crown Princess Victoria and Prince Daniel and their children Princess Estelle and Prince Oscar, Prince Carl Philip and Princess Sofia and their four children, and Princess Madeleine and Christopher O’Neill and their three children.

The king made history on September 15, 2023, when he became Sweden’s longest reigning monarch, celebrating 50 years on the throne.

He became Europe’s longest-serving monarch in 2024 when Denmark’s Queen Margrethe II abdicated the throne after a 52-year-reign.

Crown Prince Carl Gustaf - now King Carl XVI Gustaf - of Sweden in 1966. (Photo by Fox Photos/Getty Images)King Carl XVI Gustaf is Europe’s longest-serving monarch and came to the throne in 1973. (Getty)

King Carl XVI Gustaf was 27 when he ascended the throne in 1973 and is Sweden’s 74th monarch.

He came to the top job when his grandfather King Gustaf VI Adolf died, aged 90, because his father, and then heir to the throne, Crown Prince Gustaf Adolf was killed in a plane crash in 1947 in Denmark.

King Carl XVI Gustaf was just nine months old when his father died.

STOCKHOLM, SWEDEN - DECEMBER 10: (L-R) King Carl XVI Gustaf of Sweden, Prince Daniel, Duke of Västergötland, Queen Silvia of Sweden and Crown Princess Victoria of Sweden attend the Nobel Prize Awards Ceremony 2024 at Stockholm Concert Hall on December 10, 2024 in Stockholm, Sweden.  (Photo by Pascal Le Segretain/Getty Images)Sweden’s royal family is preparing to host a major event later this month. (Getty)

A year after he was crowned, Sweden’s parliament stripped the monarchy of its constitutional powers, making the monarch a symbolic head of state.

He married commoner Silvia Sommerlath in 1976, making her the first woman to wed a reigning King of Sweden in 200 years.

They had met in 1972 at the Munich Olympics where Silvia had been working as an interpreter.

Silvia Sommerlath and King Carl XVI Gustav of Sweden on their wedding day, June 19 1976.The King and Queen will then mark 50 years of marriage in June. (Gamma-Rapho via Getty Images)

The couple later had three children: Crown Princess Victoria, in 1977, Prince Carl Philip in 1979 and Princess Madeleine in 1982.

On June 19, King Carl XVI Gustaf and Queen Silvia will celebrate their 50th wedding anniversary. A day of festivities are planned for June 13, including a church service and a carriage ride through the city.

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