 Mohammad suffered from an eye affliction that rendered him nearly blind, and so in accordance with Persian Royal culture could not contend for the throne.However, following Ismail II's short and bloody reign Mohammad emerged as the only heir, and so with the backing of the Qizilbash tribes became Shah in 1578.Mohammad's reign was marked by a continued weakness of the crown and tribal infighting as part of the second civil war of the Safavid era.