The club is mainly supported by the immigrant population from the eastern region of Bengal "(known as Bangal)", who were forced to leave their homes during the partition of 1947. For those people, East Bengal Club became a source of identity and hope. The huge influx of dispossessed into the state led to a socio-economic crisis in the state. This led to rivalries among the immigrant population and native population of West Bengal in every sphere of life from jobs, and business, to schools and even on football pitches. As a result, East Bengal has a long-standing rivalry with its cross-town competitors Mohun Bagan (now ATK Mohun Bagan), which is mainly supported by the native population, with whom it competes in the Kolkata derby, Asia's biggest football rivalry. East Bengal also shares a local rivalry with another Kolkata club, Mohammedan. The club dons the iconic red and gold colours, which give it the nickname of "Red and Gold Brigade".