The South India you did not know
Elderly Tamils consider Vindhyas as Dravidian border. They proudly say they are Tamils for 2000 years & Indians only for 70 years (after independence). Their theory is that North Indians (Read: Aryans) are spoiling their culture. They stay away from Hindi, Sanskrit, Devanagari & other symbols of Aryanism. The Vindhya Range The same applies to people of Karnataka though they are not as rigid as Tamils. They too consider Sanskrit Devanagari and Hindi as symbols of Aryan "invasion". Currently both Tamils & Kannadigas are fighting the "imposition" of Hindi as national language, especially in government offices. Hindi hasn't been officially declared national language yet by any government. It is a myth spread by vested interests. Kerala is a whole different thing. It was populated with Syrian Christians for long. However, the majority now are "converted Muslims" & "converted Christians" (Read: Dalit Christians). ...