Crown Prince Frederik will take the name Frederik X. Queen Margrethe II made the surprising announcement on live TV during her traditional New Year's Eve speech.
From party prince to keen sportsman: Who is Denmark s new King? itv.com - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from itv.com Daily Mail and Mail on Sunday newspapers.
The father-of-four is widely considered to have turned his public image around from being a rebel tearaway and party boy during his youth to a family man and future king.
He’s been known as the Crown Prince of Denmark since the age of three, but on Sunday, he will leave Copenhagen’s Christiansborg Palace as King Frederik X, sovereign of Europe’s oldest monarchy.