Constantine II, Prince William's Godfather and Last King of Greece, Dead at 82

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Constantine II, the last king of Greece who spent decades in exile, has died. He was 82.

Doctors at the private Hygeia Hospital in Athens confirmed to the Associated Press that Constantine — who also became a godfather to Prince William — died Tuesday.

The former king suffered from chronic heart and mobility problems, according to Reuters. His condition had worsened, and he had been hospitalized in recent months.

He died of a stroke after being admitted to the Athens hospital last week with breathing problems, according to Greek media outlets, per The Guardian.

Constantine acceded to the throne at the age of 23, the AP reported. By then, he was already an Olympic gold medalist in sailing.

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Much of his reign was filled with political strife, and he was forced into exile by 1967.

Constantine was born in Athens on June 2, 1940, to Prince Paul and Princess Frederica of Hanover. Greek-born Prince Philip, the late Duke of Edinburgh and husband of the late Queen Elizabeth II, was an uncle to Constantine.

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The family ruled in Greece from 1863, apart from a 12-year republican interlude between 1922 to 1935, according to the AP.

The German invasion during World War II forced the royal family to flee the country, first to Egypt before South Africa and then back to Egypt.

Constantine went to boarding school and, later, three different military academies before he attended Athens Law School.

He was awarded a gold medal in 1960 at the Rome Olympics, later becoming a member of the International Olympic Committee.

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After King Paul I died on March 6, 1964, Constantine began presiding over the throne just weeks after a vote that gave control to the Center Union party over the conservatives, according to the AP.

Initially, Constantine and Prime Minister George Papandreou worked closely together but had a falling out because Constantine insisted control of the armed forces belonged to the monarchy.

Papandreou resigned in 1965. The two made a truce, and Constantine appointed a government to hold an election in 1967.

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The election favored Papandreou's left-leaning son, and so Constantine and his supported prepared an unsuccessful coup, the AP reported.

His coup having failed, he fled to Rome. The monarchy was abolished in 1973, but Constantine continued to stylize himself the King of Greece and his children as princes and princesses.

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Greece's dictatorship collapsed in 1974, and Constantine wanted to return but he was advised not to, according to the AP.

He lived most of his years in exile in Hampstead Garden Suburb in London and was said to have had close ties to now King Charles III.

He returned to live in Greece in 2010.

He is survived by his wife, the former Princess Anne-Marie of Denmark, youngest sister of Queen Margrethe II; five children, Alexia, Pavlos, Nikolaos, Theodora and Philippos; and nine grandchildren, according to the AP.