In hindsight I feel the question (though being the first result on Google for "ancient medieval india law") is too broad to be meaningfully answered in a small HSE standard post.
I have edited the question so that it focuses only on the period between the late Iron ages and early middle ages of India. I have done this because I think I should have posted two different questions --one for each period. My theory is that that this will attract more answers from people who may not be knowledgable about both periods. My other question on late middle period will follow later.
What is the opinion of the community on this approach?