 Al @-@ Tabari mentions that in 819 Abu Ishaq commanded a force sent against some Kharijite rebels . During this campaign , one of the Turkish ghilmān placed himself between a Kharijite lancer and the future caliph , shouting , " Recognize me ! " ( in Persian " ashinas ma @-@ ra " ) . To express his appreciation , Abu Ishaq on that same day granted this man the name Ashinas . In 828 , al @-@ Ma 'mun appointed Abu Ishaq as governor of Egypt and Syria in place of Abdallah ibn Tahir , who departed to assume the governorship of Khurasan , while the Jazira and the frontier zone ( thughūr ) with the Byzantine Empire passed to al @-@ Abbas . Egypt had just been brought back under caliphal authority and pacified after the tumults of the civil war with Ibn Tahir , but the situation remained volatile . When Abu Ishaq 's governor , Umayr ibn al @-@ Walid , tried to raise taxes , the Nile Delta and Hawf regions rose in revolt . In 830 , Umayr tried to forcibly subdue the rebels , but was ambushed and killed along with many of his troops . With the government troops now confined to the capital Fustat , Abu Ishaq intervened in person , at the head of his 4 @,@ 000 Turks . The rebels were soundly defeated and their leaders executed . In 831 , however , soon after his departure , the revolt flared up again , this time encompassing both the Arab settlers and the native Christian Copts under the leadership of Ibn Ubaydus , a descendant of one of the original Arab conquerors of the country . The rebels were confronted by the Turks , led by Afshin , who engaged in a systematic campaign , winning a string of victories and engaging in large @-@ scale executions . Thus the male Copts were executed , and their women and children sold into slavery , while the old Arab elites who had ruled the country since the Muslim conquest of Egypt were practically annihilated . In early 832 , al @-@ Ma 'mun visited the province , and soon after that the last bastion of resistance , the Copts of the coastal marshes , were subdued . 
