Chaldean Catholic Archeparchy of Kirkuk-Sulaimaniya
The foundation of the Chaldean Catholic diocese of Kirkuk has been attributed to Yohannan VIII Hormizd, who was recognised by the Vatican as patriarchal administrator of the patriarch of Babylon in 1780 and, after five decades of disputes and confrontations, as patriarch in 1830. According to the Chaldean Catholic priest Joseph Tfinkdji, Yohannan Hormizd visited the town of Kirkuk in 1789 while travelling from Mosul to Baghdad, and converted its Church of the East community to Catholicism. He is said to have consecrated a Chaldean metropolitan for Kirkuk, Mar Abraham, who resided in Aïnqawa during his reign, and died between 1821 and 1824. The source for this assertion is not clear. Abraham is not mentioned by any other source, and as Yohannan Hormizd himself (then considered by the Vatican to be merely metropolitan of Mosul) is styled 'metropolitan of Kirkuk' in a colophon of 1798, the Kirkuk region would seem to have been part of the diocese of Mosul at this period.
Sasanian civil war of 589-591
Bahram Chobin, infuriated by Hormizd's actions, responded by rebelling, and due to his noble status and great military knowledge, he was joined by his soldiers and many others. He then appointed a new governor for Khorasan, and afterwards set for Ctesiphon, the capital of the Sasanian Empire. Meanwhile, Hormizd tried to come to terms with Vistahm and Vinduyih, "who equally hated Hormozd". Hormizd shortly had Vinduyih imprisoned, while Vistahm managed to flee from the court. After a short period of time, a palace coup under the two brothers occurred in Ctesiphon, which resulted in the blinding of Hormizd and the accession of the latter's son Khosrow II (who was their nephew through his mother's side). The two brothers had Hormizd killed shortly afterward. Nevertheless, Bahram continued his march to Ctesiphon.