Conflict between the Saffarids of Iran and the Caliphate of Baghdad
محمد بن واصل تمیمی بر فارس مستولی شده بود. Al-Mut'ammad Abbasi gave Persia to Musa ibn Bagha.
Musa also sent Abd al-Rahman ibn Muflah to fight Muhammad ibn Wasil. Abdul Rahman was defeated and captured. When Ya'qub heard the news of Ibn Wasel's work rising in Sistan, he became greedy in Fars province. While Muhammad ibn Wasil was in Ahvaz, he turned to Persia and captured Persia. In 262, Yaqub left Persia for Khuzestan.
When the news reached the trusted caliph, he gave the order of the government of Khorasan, Gorgan, Tabarestan, Rey and Persia in the presence of the pilgrims, including the condition of Baghdad..
The caliph sent his brother al-Muwaffaq to fight Ya'qub. Jacob was defeated in this battle and fled.
Much of Yaghoub's property fell into the hands of Baghdad troops and was taken to Baghdad as booty.. Al-Muffaq returned to Baghdad due to illness, and Yaqub contracted colic in Gandishapur. The caliph sent a messenger to Yaqub with the charter of the province of Persia and supplication. Jacob put some dry bread, onion and sword in front of him and told the apostle: "Tell the caliph that I am sick and if I die you will be released from me and I from you, if I stay this sword will judge between us, if I prevail I will reach my palate and if I am defeated this dry bread and onion enough." Yaqub died in 265 in Gandi Shapur due to colic.
Jacob has been described as a wise and steadfast man. Hassan bin Zayd Alavi, who was one of his enemies, called him an anvil because of his endurance and stability..