ḥaydar ibn kāwūs (), better known by his hereditary title of al-afshīn (), was a senior general of iranian descent at the court of the abbasid caliphs and a vassal prince of oshrusana. he played a leading role in the campaigns of caliph al-mu'tasim, and was responsible for the suppression of the rebellion of babak khorramdin and for his battlefield victory over the byzantine emperor theophilos during the amorium campaign. eventually he was suspected of disloyalty and was arrested, tried and then executed in june 841.