As reports of an imminent engagement started to make the rounds in the U.K. in early 2007, William broke up with his college sweetheart after four years together.
That June, however, he invited Kate to a costume party at his barracks in Dorset (his first military posting was with the Blues and Royals of the British Army's Household Cavalry) and apparently her sexy nurse outfit was the shot in the arm the future king needed.
A few years later, William proposed with the 12-carat Ceylon sapphire ring that belonged to his late mother, Princess Diana, and the couple's engagement was announced Nov. 16, 2010.
When looking back at their brief split, William said in their first joint interview, "We were both very young. We were both finding ourselves and being different characters. It was very much trying to find our own way and we were growing up so it was just a bit of space, and it worked out for the better."
Kate admitted she "wasn't very happy about it" at the time, but ultimately it made her "a stronger person."
The knot was tied April 29, 2011.