Football in India
National Football League, established in 1996 by governing body All India Football Federation (AIFF) was the first "semi-professional" football league in India. 
The League was renamed and restructured and the I-League was founded in 2006 after India's former top league the National Football League disbanded in a successful effort aimed at increasing the game in India. Links with clubs that were not in the I-League were maintained, and each season the bottom two clubs are relegated from the I-League and replaced by two from the I-League 2nd Division. The I-League is currently contested between 11 clubs. The Kolkata Derby in the I League (and other tournaments) played between Mohun Bagan and East Bengal is one of the most fierce rivalries in the world (featured in FIFA website) and one of the oldest derbies in the world (90 years). An average 80, 000 to 100, 000 supporters throng the stadium in this special fixture.
National League (English football)
Most of the National League clubs are fully professional, while most National League North and National League South clubs are semi-professional. The professional clubs are sometimes clubs which have been in the English Football League (EFL) in the past, as opposed to those which have always been non-League. The National League is the lowest of the five nationwide football divisions in England, below the Premier League and the three divisions of the EFL, and is the top tier of the National League System of non-League football. The National League North and National League South form the sixth tier of English football. The National League consisted of only one division until 2004, but expanded as part of an extensive restructuring of the National League System which took effect beginning with the 2004–05 season.