Queen Margrethe II, born on April 16th 1940, became head of Europe’s oldest kingdom on January 14th 1972 following the death of her father, Frederik IX.
Just two reigning monarchs outstrip her longevity:
Elizabeth II, almost 70 years
Britain’s Queen Elizabeth II came to the throne on February 8th 1952 at the age of 25, making her the world’s longest reigning monarch.
Brunei’s Hassanal Bolkiah, 54 years
Sultan Hassanal Bolkiah, 75, is one of the richest people on the planet. He has reigned over the small enclave on the north coast of Borneo since his father abdicated in October 1967.
Sweden’s Carl XVI Gustaf
Not far behind is Sweden’s King Carl XVI Gustaf, 75, who has reigned for 48 years. He is Queen Margrethe’s first cousin.
The modern record is held by Thailand’s King Bhumibol Adulyadej, crowned under the name of Rama IX in June 1946. He reigned for 70 years and four months before dying in October 2016.
The French “Sun King” Louis XIV, who reigned for 72 years between 1643 and 1715, holds the record for the longest reign in recorded history.