luckily for shahrbaraz, a civil war began in 628 that divided the resources of the sasanian empire, and a devastating plague in the western provinces killed half of the population along with kavadh ii, weakening the empire. shahrbaraz marched towards ctesiphon with 6,000 men, besieged it and then captured it, betraying the sasanian nobles and killing many of them, including two notable ones named ardabīl and mah-adhur gushnasp.