Probably a stalemate during the Ridda Wars that occurred immediately after the death of Muhammad when several others claimed Prophethood or reigned on their Muslim commitments or just rebelled. For that Khalid must die.
Probably a stalemate during the Ridda Wars that occurred immediately after the death of Muhammad when several others claimed Prophethood or reigned on their Muslim commitments or just rebelled. For that Khalid must die.
Well, there was already even OTL a degree of cooperation between Heraclius and Yazdegerd and so it really depends if the situation for Yazdegerd has become better or worse. As by his time the Sassanid state was slipping toward fragmentation.