The Danish Queen, 81, ascended to the throne at age 31 in 1972 after her father's death, and January 14 will mark half a century since Margrethe stepped up to lead the country while a mother of two little boys.
Speaking to Danish magazine Billed Bladet, Margrethe reflected on Frederik's death age 72 and recalled burying the grief of losing him in favour of the "greater" task of leading Denmark's monarchy.
"My father was very keen that I should one day follow him. He was infinitely proud of that thought," Margrethe said during the interview.
Margrethe and her husband Prince Henrik's lives were changed forever when she inherited the throne just two weeks after Frederick IX died — making her Denmark's first female monarch since Margrethe I, who ruled until 1412.
The monarch had two young sons, Prince Joachim, then aged two, and Prince Frederik, three, when she was crowned the Danish sovereign.
While the pain of losing her father suddenly was immense, Margrethe knew she must put that aside to lead the people of Denmark.
"Such is the course of life in a family like mine, where one follows the previous generation upon death," Margrethe said.
"It belongs as it were, and at that moment the task is much greater than the immediate grief of losing [my] father."
Margrethe previously spoke about Frederik IX's sudden death from pneumonia in 1972 in a 2019 interview with Danish magazine ALT, recalling the moment she realised the gravity of her new role as Queen.
"We said goodbye to him at the Municipal Hospital, and I went back to Amalienborg, where the guard lieutenant from the royal guards," Margrethe said.
"The major and the banner-officer brought the royal flags from my father and mother's part of the castle, walked across the castle square and brought the flags to my rooms in Amalienborg castle as a visible sign that the burden of being monarch was now mine.
"It was in many ways an emotional moment. I was afflicted with grief and had just said goodbye to my father, and half an hour later, I received the lifeguard's flags and was very conscious that now this was serious. Now it was time to step up!"
Margrethe posed for a portrait alongside her pet dachshund at Amalienborg, the Danish royal family's residence in Copenhagen, for the Golden Jubilee interview.
Week-long celebrations were set to take place across Denmark in early January to mark 50 years since Margrethe ascended the throne, however the royal events were delayed until later in the year due to the COVID-19 surge.
"Given the recent developments in the corona situation and the health authorities' recommendations, The Royal House is postponing the big celebrations on the occasion of the upcoming 50th Government Anniversary," a statement from the Danish Royal Household read.
"Her Majesty The Queen would still like to have a festive celebration where the Danes can participate and has therefore decided to move the majority of the events planned for January to the late summer of 2022."
Crown Princess Mary will also be celebrating a similar milestone, with February 5 marking the Australian-born royal's 50th birthday.
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