Dravidians are the original habitants of India and were forced to move down south when Aryans from Europe attacked them, says Aryan Invasion Theory (AIT). Since all Hindu religious slokas are in Sanskrit, this is being used by the hate mongers of the pro-Tamil parties to attack Hindus and claim 'Those worshipping Sanskritised texts and Gods' cannot be Tamils. For them the term 'Tamil Hindu' seems to be an oxymoron.
It is true that Vedas attained its glory during the Indus Valley civilization. But the four vedas were not written in the Indus Valley, but in the southern part of India which now lays submerged. There are ample proofs to support this. The Hindu King Manu whose 'Manusmriti' is the foundation for 'Hindu way of living' was a Tamil King. As per puranas, Manu became the progenitor by saving all the sepcies of this world. He carried one specimen of each living soul in a pot and placed it a big boat which was pulled by Lord Vishnu who took the avatar of Matsya. The place where life again started after the deluge subsided is Kumbakonam (literally means mythical pot). The Noah's ark story from the Bible also corroborates that such a deluge happened in the ancient past.In Tamilnadu all of us know that the first two tamil-sangams sank under the sea (because of a deluge) which forced the Pandya Kings to establish Madurai as the Kingdom's capital and thus started Sangam 3.Many historians from the west also now agree that a land mass existed beneath the present tip of India and prefer to call it Lemuria whereas we call it the 'Kumari Kandam'. Tha Pandya kingdom existed much before the Cholas and the Cheras and that is why we do not see any architectural work of them. It is even claimed that a Pandya Kind went for the svayamvar of Sita.The word 'Pundit' meaning 'learned man', some say comes from the word Pandya. So the Pandya kingdom existed much before the Indus Valley civilization and Manu belonged to this. Tamil was a fourishing language from many many ages. A language was necessary to recite slokas and religious chants, speifically to chant 'Ga, Ha e.t.c'. This resulted in the birth of Sanskrit and both the languages co-existed in a healthy way
It is in this juncture that the great floods happened forcing Manu to move North and he laid a rule that nobody should cross the Vindhiyas as the land mass is surrounded by water below that. Then came the Indus Valley civilization and the birth of Vedas as Sanskrit attained its glory.As years passed and all the fury of nature subsided, people started moving south and Tamizh Sangam 3 was established in Madurai. Then came the Tholkappiam and all other great literary works.With the Aryan Invasion theory debunked since all Indians have the same DNA and also with different proofs pointing to a much older and bigger civilization down south, the only logical explanation that can be given is people from the south who spoke Tamizh formed Sanskrit