Harry, 38, and Chelsy, 37, first crossed paths in South Africa in 2004, and after meeting, he called her up one day to have dinner.
"Unlike so many girls I met, she wasn’t visibly fitting herself for a crown the moment she shook my hand. She seemed immune to that common affliction sometimes called throne syndrome," he recalled in his memoir of how they began dating.
"I’d always wanted to know what it might be like to meet a woman and not have her eyes widen at the mention of my title but instead to widen them myself, using my mind, my heart," the father-of-two continued. "With Chelsy, that seemed a real possibility."
The couple tried to keep things out of the spotlight, but the Duke of Sussex made a rare comment about the businesswoman while celebrating his 21st birthday in 2005.
"I would love to tell everyone how amazing she is. But, you know, that is my private life and once I start talking about that, then I've left my own self open, and if anyone asks me in the future, then they'll say 'Oh well hang on, you told them but why aren't you telling us?'" he explained to the media.
Since Harry began military training and Chelsy went to college, they often struggled with the long distance, leading to them breaking up more than once.
Amid their ups and downs were several special moments, including Chelsy acting as Harry's date to Peter Phillps' 2008 wedding.
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In 2010, the duo parted ways for good, as the blonde beauty admitted she wasn't able to hand living such a public life.
Nonetheless, Harry decided to invite his ex-lover to his and Meghan's 2018 wedding, and prior to the ceremony, an insider claimed he spoke to Chelsy on the phone.
"It was their final call, a parting call in which they both acknowledged Harry was moving on. Chelsy was quite emotional about it all," the source told Vanity Fair. "She was in tears and almost didn’t go to the wedding. In the end, she went and promised Harry she wouldn’t try and gatecrash the party."
The exes' relationship was brought up in High Court earlier this month, as Harry is suing Mirror Group Newspaper for allegedly hacking his phone years ago to obtain private information for their stories.
The Duke of Sussex pointed to an old article that detailed how the pair argued over the phone after Harry was reportedly caught flirting with another woman while Chelsy was out of town. He explained that no one else knew about his "stupid decision," which is why he believes his phone was tapped.
However, reports noted that while testifying, Harry never clarified what his "stupid decision" actually was.