Seems like the precursors might have originated from India but what would evolve into what we today call "Chess" seems to have been taking shape in Persia (Iran).
Do the historians who track these things have some metric that they determine that separates 'precursors' from the game itself or is it a human "you know it when you see it" or consensus? Just curious. I imagine it's something similar to how we answer the question "Are these distinct species?" (which doesn't really have a great answer).