He is mentioned as being in Iraq in 817, when he played a small role in supporting the anti-caliph Ibrahim ibn al-Mahdi.
His governorship of the province proved to be extremely tumultuous, and he was soon accused of treating the Yemenis in a harsh manner.
Affairs in the province eventually became so disorderly that al-Ma'mun decided to dismiss Ishaq, and Muhammad ibn Nafi' was appointed as governor in his place.
[2] In 830, Ishaq was selected to lead the pilgrimage,[3] and around the same time, he was re-invested with the governorship of the Yemen in order to fill the political vacuum that had prevailed in the region following the killing of Abu al-Razi Muhammad ibn 'Abd al-Hamid.
Ishaq accordingly made his way to the province and established himself in Sana'a, but took no action against Abu al-Razi's killer, the rebel Ibrahim ibn Abi Ja'far al-Manakhi, who was allowed to maintain his position in the southern highlands.