This was in no small part thanks to the input of their charismatic Italian manager, 54-year-old Claudio Ranieri.
Following the victory, newspapers across the world have lavished praise on Ranieri, who when he took on the role of managing Leicester last summer, was considered to be "past it".
Italian papers have proclaimed him 'King Claudio', while TuttoSport lauded him as 'the King of England.'
Prime Minister Matteo Renzi even chipped in, boasting that an Italian had been responsible for the greatest ever story in English football.
But who is Claudio Ranieri? And what's all the fuss about?
Do we have to? I hate football...
Whether you like football or not, everybody can appreciate the fairy-tale nature of Leicester's triumph.
In the entire history of the Premier League era, the trophy has only been won by five different teams, whose rise to success has been precluded by monstrous injections of cash by billionaire investors.
Ranieri's Leicester was assembled for €68.8 million, which in football terms is not a lot.
Last year's champions, Manchester City, have spent an eye-watering €530.6 million on their squad, but were still beaten to this year's title by Leicester, a team which survived relegation to the second division last year by the skin of their teeth.
This season, when Ranieri took the helm of the struggling club, nobody thought he could ever help the team win the league, with bookmakers pitching Leicester at 5,000-1 for the title back in September.
Is that why I've never heard Leicester?
Probably, yes – but don't worry about it. They might be English champions, but the majority of Italians still struggle to pronounce the team's name – as the video below shows.
So what has Ranieri said about his team's success?
“I never expected this when I arrived. I'm a pragmatic man, I just wanted to win, match-after-match, and help my players to improve week after week,” he said in a statement after the team were confirmed champions.
He has unsurprisingly resorted to talking in terms of food – comparing his team to pizza - when asked about the squad's endless winning streak.
‘It’s the team spirit, and the players enjoying training. They know they can work hard and enjoy. A little bit of luck is important. Luck is the salt, the fans are the tomato – with no tomato there is no pizza."
Finally, being a family man, he heaped praise on his Italian wife, Rosanna – a furniture dealer from Rome - for putting up with his passion for so long.
“She’s suffered a lot for me. She doesn’t like football. She likes top quality furniture, I like top quality footballers.”
Can he really become the King of England?
Don't be daft. However, The mayor of Leicester promised last week to rename streets in the town after the team and manager if they won the title, so Leicester will soon have a Ranieri Road.