Why 2023 Is a Milestone Year for Sweden's King Carl XVI Gustaf

Thron Ullberg/Kungl Hovstaterna

While 2022 was a big year for royal anniversaries — with Queen Elizabeth II of Britain marking 70 years on the throne and Queen Margrethe of Denmark celebrating 50 years of her reign — it's King Carl XVI Gustaf of Sweden's big year in 2023.

The Swedish monarch marks 50 years as head of state this year. The King, who is already Sweden's longest-reigning monarch, acceded the throne on Sept. 15, 1973, when he was just 27 — and the anniversary will be marked with two days of celebrations in Stockholm. According to the palace, a service will be held at the Royal Palace Church on Sept. 15 in addition to King Carl XVI Gustaf receiving a singer's tribute and overseeing a changing of the guard. The same night, an anniversary dinner will be held.

On Sept. 16, the King will be joined by Queen Silvia in a procession through Stockholm.

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CHRISTINE OLSSON/TT NEWS AGENCY/AFP via Getty

To ring in the milestone year, the Swedish palace released a new portrait of King Carl XVI Gustaf taken by photographer Thron Ullberg. He posed next to a silver throne, which was a gift from the Council of Parliament Magnus Gabriel de la Gardie to Queen Kristina for her 1650 coronation.

The King wore an admiral's uniform adorned with Swedish chivalry orders for the portrait.

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Carl XVI Gustaf's great-grandfather, King Gustaf V, was Sweden's monarch when he was born on April 30, 1946. Although Carl Gustaf was the youngest of five children, he was the only son of Sweden's Prince Gustaf Adolf and Princess Sibylla, jumping his sisters in the line of succession to the throne.

Carl Gustaf's father died in a plane crash at Copenhagen Airport in 1947, when the future monarch was just 9 months old, making him second in line to the throne. His great-grandfather died when he was just 4 and his grandfather became monarch, moving him to the spot of heir apparent. Carl Gustaf became King of Sweden upon the death of his grandfather in 1973.

JONATHAN NACKSTRAND/AFP via Getty Princess Estelle, King Carl XVI Gustaf and Crown Princess Victoria

King Carl XVI Gustaf and Queen Silvia have three children: Crown Princess Victoria, 45, Prince Carl Philip, 43, and Princess Madeleine, 40.

Although Princess Victoria has a younger brother, Prince Carl Philip, her place as heir formally went into effect in 1980 with the parliamentary change to the Act of Succession that introduced absolute primogeniture. When she accedes to the throne, Victoria will be Sweden's fourth queen regnant and the first since 1720.

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Princess Victoria's 10-year-old daughter, Princess Estelle, is currently second in the line of succession to the Swedish throne.