On September 16, 2000, 28-year-old Mary Donaldson went for dinner at Sydney restaurant and bar, Slip Inn. At the time, she was working for the real estate company Belle Property as a sales director and attended the venue with her roommate and a friend.
That same night, 32-year-old Prince Frederik attended that same bar with various royal friends, as they were visiting Australia for the 2000 Sydney Olympics.
They met up with Prince Felipe of Spain, who knew the sister of Mary's roommate. Prince Frederik introduced himself to Mary as "Fred".
"The first time we met, we shook hands," the now Princess told Jens Andersen, the author of Prince Frederik's authorised autobiography, Under The Bar. "I didn’t know he was the Prince of Denmark. Half an hour later, someone came up to me and said, 'Do you know who these people are?'"
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When Andrew Denton asked Mary about their first encounter in 2005, she said, "I gave Frederik my telephone number and he rang me the next day, so you could say something clicked. It wasn't the fireworks in the sky or anything like that but there was a sense of excitement."
Soon after, Mary and Frederik started a long-distance relationship. There were many phone calls, letters and low-key catch-ups out of the public eye.
But on November 15, 2001, the Danish magazine Billed Bladet outed Mary as Frederik's girlfriend and a month later, she moved from Sydney to Copenhagen. She started working at Microsoft and learning the language.
It was quite the adjustment.
"I did experience a feeling of loneliness – short-term – when I first moved to Denmark," she told the Australian Women’s Weekly.
"Moving to Denmark was a huge change in my life – a new culture, new language, new friends, and another way of life," she added.
"So, I see it as quite natural that at times I felt quite alone or a little bit like I was on the outside looking in."