It operates as a system of promotion and relegation with the Indian Super League (ISL) and the I-League 2.

[2] The competition was founded in 2007 as the successor to the National Football League, with the first season starting in November 2007.

Churchill Brothers, Mohun Bagan, Bengaluru and Gokulam Kerala have won the league twice.

[10] The league also announced a change in their foreign-player restrictions with the new rule being that all the clubs could sign four foreigners – three non-Asian and one which must be Asian.

[12] The original ten clubs in the I-League's first season were Air India, Churchill Brothers, Dempo, East Bengal, JCT, Mahindra United, Mohun Bagan, Salgaocar, Sporting Goa and Viva Kerala.

The match, which took place at the Fatorda Stadium in Margao, ended 3–0 in favour of Dempo with Chidi Edeh scoring the first goal in league history in the third minute.

[16] Bhaichung Bhutia, then captain of the India national team, said that it was the federations job to spread the game across the country and that it needed to happen.

In order to make this happen Salgaocar, Viva Kerala, Pune, and Shillong Lajong were all promoted from the 2nd Division to the I-League.

[14] On 9 December 2010 the All India Football Federation signed a 15-year, 700-crore deal with Reliance Industries and International Management Group of the United States.

[20] Two months later, on 8 February 2011, it was reported that twelve of the fourteen I-League clubs held a private meeting in Mumbai to discuss the ongoing issues related to the league.

[22] At this time however there were rumours that IMG-Reliance had been planning on revamping the I-League along the same lines as Major League Soccer of the United States for the 2012–13 season.

[26] Despite the ongoing war between the AIFF, IMG-Reliance, and the IPFCA, the league did manage to improve its product on the field and awareness did increase during this period.

It all started when the India national team participated in the AFC Asian Cup in 2011 for the first time in 27 years.

Subrata Pal, of Pune gained the most popularity after his impressive performances in goal for India during the Asian Cup.

On 20 November 2011, 90,000 people watched at the Salt Lake Stadium as Mohun Bagan defeated East Bengal 1–0.

[30] The league also saw more expansion to others areas with the promotion of United Sikkim from the 2nd Division,[31] however, their reign was short lived as financial troubles saw them relegated the next season.

During this period plenty of Indian players were wanted on trial by foreign clubs, mainly in Europe.

After his return from MLS, Sunil Chhetri and international teammate Jeje Lalpekhlua were called for trials at Scottish Premier League side Rangers in 2011.

[34] And Gurpreet Singh Sandhu underwent trials at then Premier League side Wigan Athletic and finally signing for Stabæk Fotball, Norway in 2014.

Former A-League player of the year and Costa Rican international Carlos Hernández signed with Prayag United before the 2012–13 season from the Melbourne Victory.

[39] In the month of June, IMG–Reliance, the AIFF and the I-League representatives, met with the AFC in Kuala Lumpur in order to find a new way forward for Indian football.

[42] On 14 October 2019, the AFC held a summit in Kuala Lumpur, chaired by the AFC Secretary General Windsor John, which involved key stakeholders from the AIFF, the FSDL, the ISL and the I-League clubs, and other major stakeholders to propose a new roadmap to facilitate the football league system in India.

[55] The league is currently without a title sponsor, as Hero decided not to renew its sponsorship deal with Indian football after 2022–23 season.

[58] This has bought about a lot of controversial news, most recently being when Churchill Brothers won the I-League after the 2012–13 season with Subhash Bhowmick not winning the "Coach of the Year" award, due to being listed as the technical director.

[99] Bengaluru is the only I-League club to reach the AFC Cup Final in 2016 but lost to Al-Quwa Al-Jawiya of Iraq.