From 19th century, there are extensive research on ARYANs. The term Aryan has been attributed for people ( race ), due to philological research of Dr Bopp. This famous philologist found that many of this European languages ( German, Italian, Greek, French etc ) and Sanskrit has a close affinity. ( Also all Indian languages have close affinity to Sanskrit. ).
That provoked a thought, how Sanskrit ( which is linked to European languages ) came to India ? Only through an invasion of Sankrit speaking people. Who are they ? They are Aryans. ( As the word Arya is meant and used many times for higher ranking, higher duty etc ). A simple mechanical theory for a gigantic event in history !!
If they came from outside, what was their ancestoral home location? Bal Gangadhar Tilak proposed the home of Aryans to be Artic. He based that on the astronomical evidence from Vedas.Gafurov says they came from Central Asia. Bongard-Levin says they were living between Deniper and Ural mountains in southeasten Europe.Max Muller who was a great believer and propogating Aryan theory, intially proposed the Europe region as their ancestoral home.
Swami Vivekananda says " Various theories of the original home of Aryans are prepounded by scholars according to their particular fancies.There is nothing to prove that the Aryans ever came to India from outside. So also the theory that few Aryans from North India settled down in South and dominated over millions ( of Dravidians, this is my addition to make the point clear ). This is impossibility..."
Even Max Muller, after all his research at the end concludes that Aryans are not a race. "Aryan, in scientific language, is utterly inapplicable to race....I have declared again and again that if I say Aryan, I mean neither blood nor bones nor hair nor skull...To me an ethnologist who speaks of Aryan race, Aryan blood , Aryan eye or hair is as great sinner as a linguist who speaks of dolichocephalic dictionary or brachycephalic grammer". He also mentions that all evidence of their home points Eastwards, where as none that can point to Europe or Germany or Scandinavia.
There are no evidence for Aryan Invasion into India. There are no archealogical proof. Check on "From London came the ARYANS".
Ok, we got all things correct so far. But yet something is not answered so far. Who are the Aryans anyway ? "Arya" is derived from root "Aer ". Aer ( ஏர் ) is the Tamil word for plough, which is related to cultivation. As the mandkind progressed , from nomadic to settlements, cutivators were regarded high in society. ( Since they had cattle, land and above all the foodstock ). Aryans are Tamil people who had migrated to North and have developed Sanskrit for religious purposes.
Vedic scholar Aurobindo says that Tamil and Sanskrit has lot of affinity, and they might have derived from the same roots.
Has the TAMILS developed SANSKRIT ?