Who are the Indo-Europeans who migrated to India around 1000 B.C.?

Question

Who are the Indo-Europeans who migrated to India around 1000 B.C.?

Answer 1

They were the Aryans who previously inhabited south-western Russia. They invaded India and consequently peeled back the range of the already established ethnic group the Dravidians. The Indo-Europeans today constitute a majority of Europe's ethnic origins that include the Celtic, Slavic, Germanic, and Latin peoples. Furthermore, much of the Hindu culture you see in India today are Indo-European in origin. Consider this:

the Hindu word for king is Raja, in Spanish Rey, etc.

Answer 2

The Indo-Europeans that migrated to India were part of the larger Indo-Aryan subfamily.  The Indo-Aryans did not invade India. Rather they migrated there and their pastoral culture allowed them to dominate the Dravidians through language, business, and religion.

The first evidence of their language and people is in the Mittani treaty of northern Syria in 1600 BC.  This treaty was between the Mittani, a non-Indo-European kingdom in Syria, and the Hittites.  The treaty includes a list of Gods that the signers invoked to proclaim their faithfulness.  The interesting thing is that among the Gods are Indra and other Vedic Indian names.  Also the name of the Mittani King was clearly an Indo-Aryan name, not a Semitic name like we would expect.  This is the first evidence of Indo-Aryan language and people.

The Indo-Aryans then migrated to Iran and India, sometime after the Mittani treaty, but well before 1000 B.C.

The first evidence we have of them in India is the Rig Veda, the first Vedic Sanskrit book which was composed around 1300 B.C, but not written down until a few hundred years B.C.

In the Rig Veda the Indo-Aryan migrants differentiate themselves from the native Dravidians/Harrapans descendants by calling themselves Aryas (true Arya also meant noble, but in the earliest texts it has a clear ethnic/linguistic meaning).  They called the native Indians Dasyus.

The early Aryas were a pastoral people who traveled between Dasyu cities and traded.  Because of this it was necessary for the Dasyus to learn Sanskrit and/or Prakrit(s) in order to trade.  Along with langauge, the Dasyus also adopted the Aryas religion and culture though much of Dasyu culture and even some language influenced the Aryas (the retroflex letters in Sanskrit are a Dravidian influence).  Thus the Arya culture replaced much of the Dasyu culture in Northern India.

The Vedic religion in the Rig Veda could most easily be described as pagan.  It was not yet the refined philosophy of the Bhagavad Gita or the upanishads (though it was close).  It was focused on the worship of patron gods and nature.  The sacrifice involving fire (agni), Soma (ambrosia, presumably a variant of the lotus), and occasionally animals was the dominating feature of early Vedic religion.  The Rig Veda is filed with many hymns to gods like Indra and even sheds some light on the relationship between the Aryas and the Dasyus (in some instances Indra "smites" the Dasyus).

I hope this helps.  If you find it interesting you should read

"Indo-European Language and Culture" by Fortson

or a translation of the Rig Veda