After the sack of Mosul, the Mongol army led by Samdaghu besieged Jazirat Ibn ʿUmar until the summer of 1263; the siege was lifted and the city spared when the Church of the East bishop Henan Isho claimed to have knowledge of chrysopoeia, and offered to render his services. Jemal ad-Din Gulbag was appointed to govern Jazirat Ibn ʿUmar, but he was later executed for conspiring with the city's former ruler Ishaq, and was replaced by Henan Isho, who was also executed in 1268, following accusations of impropriety.
Following the siege of Mosul, the Mongol forces under Samdaghu besieged Jazirat Ibn ʿUmar until summer 1263; the city was spared when Henan Isho, the Church of the East bishop, claimed knowledge of chrysopoeia and offered his services. Jemal ad-Din Gulbag was appointed to govern Jazirat Ibn ʿUmar but was executed for conspiring with Ishaq, who had previously ruled the city. Henan Isho, also accused of misconduct, was later executed in 1268.