At the end of February 2015, Leicester City were at the bottom of the Premier League. A year later, they are at the top, with legitimate hopes of winning the title for the first time in the club’s 132-year history. Their intoxicating rise has many causes: the counterattacking style introduced by their manager, Claudio Ranieri; superb performances by Kasper Schmeichel, Jamie Vardy and Riyad Mahrez; a scouting network that identifies undervalued players. Yet their success is also underpinned by the Premier League’s huge wealth and the egalitarian way in which that wealth is shared.

In previous seasons, a side such as Leicester City might have been compelled to sell Vardy, the striker who scored in 11 consecutive matches last autumn. Now, they can afford to give him a contract that is reportedly worth £80,000 per week. Other teams that are outside the established elite are also asserting their financial clout: Stoke City have just spent £18.3m on the French midfielder Giannelli Imbula, breaking a club transfer record set just five months earlier.

Even for middling teams, huge figures are the new normal. According to Deloitte, 17 of the 30 highest-earning clubs in the world last season were from the UK, up from eight two seasons earlier. The Premier League made as much from TV rights as the next three highest-grossing leagues combined: Serie A in Italy, La Liga in Spain and the Bundesliga in Germany. Only Barcelona, Real Madrid and Juventus earned more from domestic rights than the last-placed Premier League team.

The English league’s financial dominance is expected to grow. The UK rights to screen Premier League football between 2016 and 2019 were sold for over £5bn last year – an increase of 70 per cent on the previous deal. “Am I surprised? Of course, the little old Premier League [is] doing quite well,” said Richard Scudamore, the league’s chief executive. It is also gaining ground abroad. Overseas rights, worth £7.6m when the Premiership began, will exceed £1bn per year from 2016-17, with potential for growth in the United States and in China.

Overall, TV rights for the 2016-19 seasons sold for £8.5bn, compared to £5.4bn for 2013-16. Deloitte predicts that all 20 Premier League sides could be among the richest 30 in the world from next year. “You have a perfect storm – more money will lead to better players, higher wages and more exposure,” says the sports economist Rob Wilson.

The way in which the league divides its wealth has enabled lesser sides to join the sport’s financial elite. Proceeds from its huge broadcasting deals are divided more equally than in any other major European league. In La Liga last season, the title winners, Barcelona, earned 11.6 times more than the last-placed SD Eibar but the English champions, Chelsea, received only 1.53 times more than the bottom-placed Queens Park Rangers.

The rise in overseas TV rights has been integral. Overseas rights were worth a fifth of domestic rights from 1992-97 but are now worth two-thirds. Unlike domestic rights, they are divided equally. As a result, the ratio between what the top- and bottom-earning clubs in the Premiership receive from TV rights has almost halved, from 2.7 to 1.53, since the league’s first season in 1992-93.

TV rights now form a larger percentage of each club’s overall revenue. Some clubs earn three-quarters of their revenue from domestic rights – a boon to sides such as Leicester and Stoke. At the same time, the financial advantage that English heavyweights used to derive from sponsorship, merchandise sales, match-day revenue and cash from the broadcasting of European competitions has become less important. “The acceleration of TV money in the Premier League has begun to close the gap between the elite and mid-ranking teams,” Wilson says.

While Leicester City’s rise has been extraordinary, it may herald a new age of unpredictability. It is not only a vindication of Ranieri and his club, but a model for redistributing football wealth more equitably.