Scotland's and Scandinavia's histories have long been intertwined with smatterings of Old Norse in the language, Viking and Norse settlement - and the suggestion Orkney might join forces with Norway.

Now a Scot will sit on Denmark's throne - well, sort of.

Queen Margrethe II of Denmark unexpectedly announced her abdication on Sunday, handing in her two week's notice from her role as Europe's longest-reigning monarch.

The 83-year-old will be succeeded in mid-January by her son, Crown Prince Frederick, and his Australian-born wife Crown Princess Mary, who has Scottish parents.

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Her abdication came as a shock to Denmark's citizens; the Queen is a popular figure after remodelling the monarchy for the modern age with her mix of humour, smart public engagement and her 60-a-day cigarette habit.

Denmark's Queen Margrethe II announced on Sunday that she plans to leave the throne to make way for her son, Crown Prince Frederik.

The queen announced during her New Year's speech that she would abdicate on January 14, which is the 52nd anniversary of her own accession to the throne at age 31 following the death of her father, King Frederik IX.

Margrethe, 83, said the back surgery she underwent in early 2023 led to "thoughts about the future" and when to pass on the responsibilities of the crown to her son.

"I have decided that now is the right time," she said in her speech.

The queen's announcement made up only a few sentences at the end of her wide-ranging New Year's speech which reflected on the "turbulence and upheaval in the world" amid the wars in the Middle East and Ukraine, and the climate crisis.

But she also thanked her nation's people for "the warmth and hospitality I meet with everywhere in Denmark".

Danish Prime Minister Mette Frederiksen confirmed the decision in a news release that paid tribute to the monarch, offering a "heartfelt thank you to Her Majesty the Queen for her lifelong dedication and tireless efforts for the Kingdom".

The Herald:

Margrethe is the "epitome of Denmark" Ms Frederiksen's statement read, and "throughout the years has put words and feelings into who we are as a people and as a nation".

Her successor was born Mary Donaldson to Scottish academics who had emigrated to Australia and she grew up in Tasmania.

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Crown Princess Mary has British citizenship and worked for three months in Edinburgh as an account manager at an advertising agency.

She met her future husband the old fashioned way - on a night out in a pub in Sydney during the 2000 Olympic Games - and they married in 2004 before having four children.

Scandal has recently followed the couple with Spanish-language papers printing photographs of Crown Prince Frederik out on the town with a Mexican socialite in October last year.

Mary has big shoes to fill.

The six-feet-tall Margrethe has been one of the most popular public figures in Denmark. She often walked the streets of Copenhagen virtually unescorted and won the admiration of Danes for her warm manners and for her talents as a linguist and designer.

A keen skier, she was a member of a Danish women's air force unit as a princess, taking part in judo courses and endurance tests in the snow.

In 2011, at age 70, she visited Danish troops in southern Afghanistan wearing a military jumpsuit.

As monarch, she crisscrossed the country and regularly visited Greenland and the Faeroe Islands, the two semi-independent territories which are part of the Danish Realm, and was met everywhere by cheering crowds.

Denmark has Europe's oldest ruling monarchy, which traces its line back to the Viking king Gorm the Old, who died in 958. Although Magrethe is head of state, the Danish Constitution strictly ruled out her involvement in party politics.

Yet the queen was clearly well-versed in law and knew the contents of the legislation she was called upon to sign.

She received training in French and English from her early years, as well as Swedish from her mother.

In addition to archaeology, she studied philosophy, political science and economics at universities in Copenhagen, Aarhus and Cambridge along with the London School of Economics and the Sorbonne in Paris.