^ I don't discount the Aryan invasion theory, I just dispute how it's used by a lot of white nationalists. People like this will claim that Indian civilization is just the result of white people, and that it fell into corruption after they mixed with the local Dravidians. The roots of ancient India (or ancient Egypt, or Sumer, or Mesoamerica, or any number of ancient civilizations) have nothing to do with "white" people, let alone ancient Europeans.
It's very possible that Indo-Aryans/Indo-Europeans steadily migrated into India or even invaded parts of it over a certain period. What is less certain is what this migration actually looked like -- the earliest Hindu text (Rigveda) for example was clearly written after this migration had taken place (it references animals like elephants that wouldn't have existed outside of India or Africa) -- and exactly what effect this had on ancient Indian society. Overall, it's an incredibly murky period in history from which almost no one can draw any serious conclusions. This also means that it's not even clear if the Indo-Aryans were "white" in the conventional sense, or whether modern Europeans can really draw much of a connection to them.
All in all, associating these ancient civilizations with white people or with Nordics is immature. Yes, there are linguistic ties with the ancient Germans and Scandinavians -- but that doesn't prove that the roots of Indian civilization are Nordic. Also, the Aryans are supposed to come from Central Asia, after which they invaded India, Iran, and Europe. I'm unaware of Central Asians (Kazakhs, Uzbeks, etc) being "white". On top of that racial compositions have changed over time -- Latinos for example did not exist before 1600 C.E. It's possible that the Aryans had a phenotype that would be unrecognizable today.