"So based on your statement, is the aryan invasion then the first known caste of instilling caste-dom?"

* no, it is another example of it and thought it was interesting in the light of the positive light that the old testament shine on Persian/Aryan rulers.

"Do we have concrete evidence that aryans carried a doctrine/divine-based philosophy of indians being beneath them in terms as human beings?

In other words, what would indicate an "aryan supremacy" mindset during that time?"

* certain african scholars point to the invasion of india by the aryans and the low caste position of the darkest and blackest in the lowest caste to be indications of a supremacist mindset.

"There have ALWAYS been invasions for whatever purposes, mainly the proximity to natural resources (hunting/gathering/farming/agriculture, water) and there has been intermingling. It is said that is why indians have dark features and straight hair.

Normans vs. Scots...Karibs vs. Arawaks...Apache vs. Miami

But can we say that there was a BLOOD PURITY/EXCLUSIVIST doctrine within germanic and aryan history as practiced by the semites?"

* In German, no. In Aryan, I don't know, but there are characteristics of a nobility system that forbids breeding and inter-marriage between castes, between the "dirty" and the "pure."

"Of your opinion/studies, what is the root of human supremacy implementations against others (as created inferiors), as encompassed within a doctrine of divine authority/sanctioning/justification?"

* so what is the ORIGINAL doctrine of this and its concrete form in a specific group that can be pointed to? i'm not 100% sure - but we can see characteristics of it in a few cultures, namely semitic and aryan.

yes there is some confusion regarding the application of the word aryan and yes the germans were using 19th century european ideas to connect themselves to the "ancient aryans."

This is interesting, look at this quote, taken from Wikipedia:

"Darius the Great, King of Persia (521–486 BC), in an inscription in Naqsh-e Rustam (near Shiraz in present-day Iran), proclaims:

"I am Darius the great King… A Persian, son of a Persian, an Aryan, having Aryan lineage..."
— Darius

And if you have the time, read through this:

"How Darius Founded Judaism."
http://www.askwhy.co.uk/judaism/index.php