Deposed by military rulers and spurned by his subjects who voted to ditch the monarchy in 1974, Constantine II was the only son of King Paul and Queen Frederica of Greece. He suffered from chronic heart and mobility problems and had been treated in an Athens hospital since last week.

“It is with deep sadness that the royal family announces that HM King Constantine, beloved husband, father, and brother, passed away yesterday,” Constantine’s private office said in a statement on Wednesday.

Constantine II, godfather to Britain’s Prince William and a second cousin to King Charles, would be buried privately in Tatoi, the summer palace of the former Greek royal family, where his ancestors are also laid to rest, the government said.