Were Aryans the forefathers of Hindus?
Preface: this answer is hugely lacking in details, which I hope to add later. For more detailed and evidence-based views on the matter, consider consulting the following discussions:
- What are the latest publications demolishing the Aryan invasion/migration theory? at History.SE (note: there aren't many, aside from some confusion about the genetic evidence as it currently stands)
- Why is Dravidian history ignored? at History.SE (tangentially-related)
- What is the current consensus on the origins of the Brahmi script? at History.SE (concerning the particular claim, currently thought to be false, that Brahmi derives from the Harappan script)
- Indians - Descendants of Indo-Europeans, IVC evacuees, Dravidians, or all of the above? at /r/AskAnthropology
- "The Aryan Migration Theory: Last Word" on Robert Lindsay's blog (but, in particular, see the two works cited at the bottom of his post)
This is obviously an issue that will provoke some heated feelings, so let me just provide a brief overview of what science has to say about the migration of peoples into northern India during the Vedic period. I will update this in more detail later, but for now, this should serve as a reasonable summary.
Much research has been done since the 19th century to firmly establish the classification of Indo-European languages. We now know that Vedic Sanskrit (the language of the Rig Veda) is part of the Indo-European family of languages, and, in particular, part of the Indo-Aryan subfamily. We have strong reason to believe that the Indo-European homeland (the "urheimat") lies near the Black Sea. This, along with other evidence, strongly suggests that the Indo-Aryan languages were brought to northern India by a migration of peoples from the northwest.
I am not well-acquainted with the archaeological evidence here, but it is known that there are archaeological traces of a migration towards the Indus Valley, and that at around this same time, the Indus Valley civilization collapsed. This is taken as evidence that the Indus Valley peoples were displaced by a migration of peoples from the northwest.
The genetic evidence is less clear than the linguistic evidence. There is some Y-chromosomal evidence that the "North Indians" and the "South Indians" (Dravidians) represent two substantially different populations. This, too, suggests a migration from somewhere into northern India.
This evidence generally favors a scenario in which an "Aryan" population migrated into northern India c. 1500 BC. It is clear that when they migrated, they brought with them religious texts - the Vedas. In this sense, the Aryans "started" Hinduism. However, even Vedic Hinduism was not purely the creation of the Aryans - there is some evidence that some practices of the Indus Valley peoples were incorporated into what we know now as the Vedic religion.
Alternates to the Aryan migration scenario exist, but I don't know much about them, and they don't appear to have much evidence supporting them.
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