I have written an introductory post (it’s free), Entering Steppelandia: pop. 7.7 billion, to a series of posts (mostly paid) that I will write about the Eurasian steppe. So I’m thinking and reading a lot about this topic. This is relevant to “Brown Pundits” because we subcontinental people have been stamped by the steppe.
First, there were the Indo-Aryans. About 15% of the ancestry of modern South Asians comes from these people (averaged across region and caste). Then there were the Iron Age Iranian pastoralists, Scythians, and assorted other related groups. There is no strong evidence right now of a major genetic impact, but I think the statistical power is not such that I can definitively ignore this possibility.
Finally, there are the Muslims. They had the least impact. But they are most reviled. Why?
They lost. The lesson is to not lose. The rest is commentary.