King Frederik of Denmark Reveals His New Signature as Monarch — Why It's Similar to King Charles

King Frederik of Denmark’s elevated royal role comes with a meaningful new signature.

On Tuesday, the Danish Royal House unveiled the King’s new way of writing his name on a 100th birthday card. King Frederik, 55, succeeded his mother Queen Margrethe as monarch upon her abdication on Jan. 14, and courtiers said he will continue the tradition of sending well-wishes for banner birthdays and wedding anniversaries.  

"On the occasion of your 100th birthday, I send my heartfelt congratulations,” read the message in a snap shared to Instagram, signed “Frederik R.” The “R” stands for “Rex,” which means King in Latin, and King Charles has signed his name the same way since he acceded to the throne in September 2022.

Queens like King Frederik’s mother, Queen Margrethe, and King Charles’ late mother, Queen Elizabeth, (who are third cousins!) have also used the regnal signature, with the “R” after their first name signifying “Regina,” meaning Queen in Latin. King Charles’ wife Queen Camilla has also signed her name as “Camilla R” since her husband’s accession, though she is a queen consort rather than a queen regnant, or female monarch. 

The stationery suite for King Frederik’s birthday card to the centenarian in Northern Jutland also included his new royal monogram. On his Jan. 14 accession day, the Danish Royal House unveiled the new cipher for King Frederik’s reign. The regal design features the letter “F” interlocked and mirrored around the Roman numeral X for 10, for King Frederik X of Denmark, below the royal crown. Just like the reign change from Queen Elizabeth to King Charles in Great Britain, Danish courtiers said that King Frederik’s cipher would slowly replace his mother’s monogram in places like military uniforms.

According to the court, the new Danish sovereign will also continue the custom of sending letters for special occasions.

"The King has decided to continue the tradition of His Majesty sending congratulations to citizens who turn 100, 105 and 110 years old. In addition, the King will also continue to send congratulations on the occasion of diamond, crown diamond, iron and nuclear weddings for 60, 65, 70 and 75 years of marriage respectively,” the Instagram caption read. 

“The tradition of greetings from the Majesty on special anniversaries goes back many years. It used to be started with telegram greetings that were sent, written down and read out to the birthday person in question on the day,” the court said.

On Jan. 14, Queen Margrethe, 83, officially stepped down as monarch by signing a declaration of her abdication during a Council of State at Christiansborg Palace in Copenhagen. Queen Margrethe abdicated on the 52nd anniversary of her accession and made history as the first Danish monarch to voluntarily step down from the throne in nearly 900 years, per Danish Royal House history.

Queen Margrethe cited health concerns in her annual New Year's speech where she first announced her shock abdication, explaining that she decided “now is the right time.”

Shortly after, the new King Frederik stepped out solo on the palace balcony. He waved to the cheering crowds gathered below, looking emotional and wiping away tears.

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Danish Prime Minister Mette Frederiksen then stepped forward and proclaimed the change of reign from the balcony, where the King made a short speech and announced his royal motto. His wife, the new Queen Mary, then appeared on the terrace of the royal residence — where they shared a surprise kiss! — and were joined by their four kids.

Queen Margrethe’s unexpected abdication, which she announced on New Year’s Eve, brought great change for Frederik and Mary’s family.

The royal couple’s 18-year-old son became Crown Prince Christian, taking his father’s former title as heir to the throne, while their three younger children Princess Isabella, 16, and twins Prince Vincent and Princess Josephine, 13, all moved up a spot in the line of succession. New portraits of the royals were unveiled a few days later, including a family shot.