Yazdgerd I ruled for over two decades in relative peace with Rome — unusual enough that contemporaries noticed. The 422 treaty ending hostilities with the Eastern Roman Empire was negotiated under his reign, and Byzantine sources occasionally referred to him, almost admiringly, as "the Sinner" for his tolerance of Christians and Jews within Sasanian territory. That tolerance was controversial enough among the Zoroastrian priesthood that later tradition blamed him for impiety, a political smear that outlasted him by centuries.
Yazdgerd I ruled for over two decades in relative peace with Rome — unusual enough that contemporaries noticed. The 422 treaty ending hostilities with the Eastern Roman Empire was negotiated under his reign, and Byzantine sources occasionally referred to him, almost admiringly, as "the Sinner" for his tolerance of Christians and Jews within Sasanian territory. That tolerance was controversial enough among the Zoroastrian priesthood that later tradition blamed him for impiety, a political smear that outlasted him by centuries.