I’m an avid Persophile, and am in the process of creating a mod for Crusader Kings III of a world where the Persians won the Byzantine-Sasanian War of the early 7th Century and thus survived into the (early) Mediaeval Era. One issue I need to change is the way succession is organised for the Sasanian Empire, as the current options are based wholly in Western Europe’s feudal traditions of Salic partitions, primogeniture, and their focus on legitimacy for heirs, all of which are largely foreign concepts to Persia in the 7th Century.

I have a fairly strong grasp on inheritance law in Persia among families, but within the context of who becomes Shah I am far less certain. It seems to have been the preferred heir of the Emperor, rather than the eldest child, and with a few exceptions the nobility just went along with it. Is this a fair way to look at it, or was there a more formalised process of seniority among heirs, or some kind of pseudo-elective process among the nobles? Or did it more accurately reflect the “Open” succession model, later seen in Islamic and Turko-Persian regimes across the Near East?