Upon his return, due to strong opposition by the opposing Patriarch, Sulaqa was imprisoned by the Ottoman leader of Amadiya, tortured, and executed in January 1555.

However, by the end of the 15th century, the Patriarch Shimun IV Basidi (1437–1493) decided to make the office hereditary in his own family,[9] the Eliya line.

As a result, Shimun IV and his successor only appointed their family members as metropolitan bishops,[10] for the uncle to choose his brothers or nephews to succeed him as patriarch.

The patriarch Shemon VII Ishoyahb, consecrated either towards the end of 1538 or early in 1539, was highly unpopular due to his illicit activities and profligate life, selling church properties, and using concubines.

The group managed to persuade the Franciscan friars that they agreed with the Catholic faith, and expressed the desire to have Sulaqa confirmed as patriarch by the pope.

On April 9, 1553, he was consecrated as bishop in St. Peter's Basilica in Rome by Cardinal John Álvarez y Alva de Toledo, OP (1488–1557) (or by the pope himself according other sources).

However, in January 1555, he was summoned, imprisoned for many months, tortured, and executed, probably by drowning, by the local pasha of Amadiya instigated by the partisans of Shimun VII.

Yohannan Sulaqa was pointedly given the title of "Patriarch of Mosul and Athur" in Rome,[23] not in a restrictive sense, but meaning of the Church of the East, and at that time, Kerala aside, was exclusive to northern Mesopotamia, the former Assyria.

[24][25] This was in reference to the Old Testament which gives Abraham's birthplace as "Ur of Chaldees" (traditionally Edessa) at a time long before the Chaldeans entered Mesopotamia.

[26][27] The term "Chaldeans" had a history of being used in an ethnically and geographically inaccurate sense by Rome, having been previously officially used by the Council of Florence in 1445 as a new name for a group of Greek Nestorians of Cyprus who entered into full communion with the Catholic Church.

This patriarchal See was initially located in Amid, but very soon moved to Siirt, then to Urmia, then to Khosrowa (near Salmas) and from the second half of 17th century to Qodchanis (now Konak, Hakkari).