The migration of Indo Europeans into India after the collapse of Indus Valley urban civilization is still the widely accepted and evidentially robust view among historians in academia.
It is true that the Kurgen
hypothesis is most widely accepted theory of Aryan origins, but it is not evidentially robust, unless you are willing to mention that evidence. The only evidence Aryan origins is based on is linguistic speculations and some guess work -- e.g. Kurgen hypothesis is based on the idea the Aryans were a horse and chariot driven war-like people that originated in Russian steeps spread across Indo-Europe wiping out the original matriarchal god-worshipping peaceful cultures.
Prior to the Kurgen hypothesis was the Anatolian hypothesis that the Aryans were from the Anatolia region. Prior to that there was the Nordic hypothesis, the Aryans were a Germanic people, blonde hair and blue eyed etc. There are many competing hypothesis claiming where they were from and each is mired in politics.
The only evidence for notion of Aryan people comes from the same evidence --- Sir William Jones noting when he studied Sanskrit, that Sanskrit was linguistically from the same family of languages that Latin, Greek and other European languages were from. While, the bulk of those languages occur in Europe, only one of then occurs in India. Hence, by posting a linguistic centre of gravity in Europe somewhere, the inference is at some point of the Aryans arrived into India from Europe, bringing with them Sanskrit and the Vedic hymns and the caste system and subjugating the native Dravidian people from India. This is why it is known as
invasion theory
In order to support this theory, Western Sanskritists, tried to find evidence of this invasion in the Rig Veda itself, especially hymns like the Battle of the ten kings which mentions the tribal battles between kings as evidence of invasion. Hymns describing how the rain god Indra slayed the demon Vrittra who had imprisoned the waters and the cattle, were interpreted as the chief of the Aryans Indra slaying the chief of the Dravidian tribes Vritra and establishing Aryan rule in India(as a justification for current colonial rule in India) was provided as flimsy evidence for the mythical invasion. But no evidence for any invasion has been found by archaeologists.
Despite there being no evidence the Aryan invasion theory, the theory was still pushed as fact. Taught as a fact Everything within Hinduism, scriptures, epigraphical records was interpreted in light of the invasion myth. Then the only archaeological evidence that did emerge later by the archaeology Sir Mortimer Williams where he discovered at Harappa the evidence of vitrified forts and dozens of skeletons seeming holding hands, was instantly taken as confirmation of how the Aryan tribes sacked the Harrapa city and again taught as fact. Later, archaeologists discovered that actually the skeletons were not holding hands, but were at different statra(i.e. different dates, some as far apart as several centuries) As you can see the myth was so taken for granted, that nobody bothered to challenge the fact that there was no evidence to back it up at all.
So no Aryan invasion theory has officially been discredited as a myth due to the total lack of archaeological evidence, it has been demoted to Aryan Migration Theory. It is basically a tacit admittance: We have no evidence for the Aryans ever coming into India, but we still believe it must have happened because of linguistic evidence.
But when the same linguistic evidence can be interpreted to locate Aryans in Anatolia, in Russian steeps, in Germany, it shows that it clearly is not certain scientific evidence at all. Obviously, everyone is guessing because they had taken the invasion for granted for so long.
Some Hindu historians in India hold a minority position that it did not happen. For some odd reasons a significant fraction of Hindus believe it matters a lot that Indo European people were in India from the stone age and did not migrate here in the late Bronze age.
This is actually more of ad-hominem attack used by people who still support some sort of Aryan invasion against scholars who oppose it, to accuse them of being Hindu nationalists etc to discredit them. In actual fact, AIT/AMT is opposed by scholars who are neither Hindu or Indian, and who were even former AIT/AMT proponents. That the most vocal of opposition comes from Indian scholars is not surprising, because Inda's real history is connected to their own identity.
We know a lot about the ancient life and culture of the Indo European people throughout central Asia from 6000 bce to 1000 bce from archaelogy whose life style is reflected in the Vedas as well as in Iranian Avesta. I would recommend reading an actual academic work " The Horse, the Wheel and the Chariot" to understand the historical evidence for these ancient people.
These old arguments of horse, chariots and wheels being evidence the Aryans came from Europe because no evidence has been found in archaeology for the same in Indus valley settlements have long been debunked. Horse fossils have been found, toy chariot/carts have been found, spoked wheels have been found. In addition to what else has been found that was thought the Aryans brought in from Europe and were not in India before then -- ritual altars like those used in Vedic sacrifices, ritual water pools, the swastika symbol, Yoga postures, including statues of Brahmin like priests wearing robes as Brahmins wear them even today. In fact, the current research shows that there is no evidence of Aryans bringing anything that we cannot already find the Indus sites. This has caused scholars to now revise the the beginning of Hinduism from 1500BCE to 6000BCE.
Here is the strongest evidence against AIT/AMT which so far has been ignored just because it contradicts the myth
1. The Aryans never mentioned in any of their literature, whether Vedic or post-Vedic, of having a home outside of India. In fact the Aryans describe their history as always being in India and trace continuous settlements of kings to 6000BCE. The Greek records agree that this is what Indians always believed.
2. The Aryans referred to India as "Aryavarta" as the land of the Aryans and never referred to any other place as being the land of Aryans
3. The oldest Aryan literature, the Rig Veda, describes the geography of India, the flora and fauna of India not Europe. It was believed before that early hymns of the Rig Veda were composed outside of India, now it is accepted the Rig Veda was fully composed in India
4. The Rig Veda describes as thriving the now dried up river of Saraswati, which was flowing from the Himalayas into the Indian ocean in 4000BCE. It is even says all its settlements are alongside the Saraswati river, which is where most of the Indus settlements have indeed been found. This means the Aryans were already millenias in India before the posited date of 1500BCE as their arrival. The drying up of the river Saraswati is later mentioned in post-Vedic literature like Mahabharata.
5. The newest kind of evidence, based on Mitochondria DNA, shows absolutely no evidence of arrival of European DNA into India in 1500BCE or even after, the earliest evidence of foreign DNA entering India is with the Greek invasions in 300BCE.
6. Astronomical tables of the Aryans record naked eye observations of the beginning of the Kalyuga age in 3102BCE Feb correct to minutes from Indian, and astronomers like Playfair who studied them declared it was impossible for this to have been known, unless it really was a naked eye observation.
7. The Indian epics actually describe migrations from India into Europe as various tribes leaving India, including the Danvas tribe(the children of the danube) but NOT migrations into India.
8. The earliest evidence of migrations into Western Asia such as Hittie-Mittani state and Indian kings appearing with Sanskrit names is from 1700BCE.
If the preponderance of evidence is considered, I think we have very good reason to suspect AIT/AMT without being a Hindu nationalist and it unfair to accuse anybody who challenges the myth to be a Hindu nationalist or just stupid.
