Entertainment Tonight reports that the happy couple said their vows in Aberdeenshire, Scotland, at a castle owned by Leslie's family.
Photos from the occasion show it to be a joyous affair, with the bride and groom grinning from ear-to-ear as they walked back down the aisle as husband and wife.
Several fellow members of the Game of Thrones cast were in attendance at the ceremony, including Emilia Clarke, Peter Dinklage and Sophie Turner.
The couple met while working on the HBO fantasy series. In fact, their characters, Jon Snow and Ygritte, were on-screen love interests for several seasons.
In 2017, Harington opened up to Entertainment Tonight about how special it was to have met his now-wife on the series.
"I think that's the really special thing about it is that we met on this show and here we are seven years down the line back here promoting season seven," Harington said. "I mean, it's mad. It's such a special thing. I'm so privileged."
The couple became engaged in September, with Harington popping the question on a romantic summer night in the country. However, he apparently had a much more elaborate plan in store for Leslie.
"I was going to string up some lights in some trees and do all the romantic stuff," Harington told The Jonathan Ross Show. "But we were in the country and we were under this beautiful night sky and had a log fire burning and red wine."
He continued, "I blew my load early. I meant to do it the day after with the lights. What I meant to say was, I popped my question a bit early."
The couple has not given to much incite into their relationship, but Leslie did open up a bit in a 2016 interview with The Telegraph. She revealed that she was "very happy" and that Harington is "a great man" despite their busy lives as actors.4comments
"I'm very proud of him," she said. "There's an understanding that comes with the job, an understanding of being busy and when you have to say 'Sorry, I'm just going to bugger off for two months to film.'"
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