Catholicoi and Patriarchs of Babylon for the Chaldeans
The Shimun line
In 1553, Mar Yohannan Sulaqa, willing to separate from the Church of the East's Patriarchal See of Alqosh, an Assyrian town in the Assyrian homeland, went to Rome asking for his appointment as Patriarch. He was consecrated in St. Peter's Basilica on 9 April 1553.
93 Shimun IX Dinkha — moved the see to Urmia, was the last patriarch of the Shimun line to be formally recognized by Rome, reintroduced the hereditary succession
97 Shimun XIII Dinkha — moved the see to Qochanis, formally broke full communion with Rome in 1692, while continuing as patriarch to be independent of the Alqosh patriarchal line. His successors in the Shimun line eventually became the sole line remaining within what later adopted the name Assyrian Church of the East
The Josephite line of Amid
The Catholic Patriarchs based in Amid, now Diyarbakır in southeastern Turkey, began with Joseph I who in 1667 became Catholic, obtained from the Turkish civil authorities in 1677 recognition of his independence from the non-Catholic patriarchal see of Alqosh, and in 1681 was recognized by Rome as "patriarch of the Chaldean nation deprived of its patriarch".
From 1830, the post of Catholic patriarch continued under Yohannan VIII Hormizd as Patriarch of Babylon and head of what is now called the Chaldean Catholic Church.
The Alqosh/Mosul line
In the 17th and 18th centuries, Alqosh was the seat of what, until the setting up of the Shimun line, had been the only patriarchal line, tracing its origins from the Apostle Thomas in the 1st century. This line is called the Eliyya line, because of the name that each of its successive patriarchs assumed. In 1771, the Alqosh Patriarch Eliyya XII Denkha entered communion with the Catholic Church. However, on his death in 1778, his successor Eliyya XIII Ishoʿyahb, after obtaining recognition by Rome, quickly repudiated the union and returned to the traditional doctrine. His cousin Yohannan VIII Hormizd professed the Catholic faith and won others to the same faith. When Eliyya IX Ishoʿyahb died in 1804, no successor was elected and Yohannan Hormizd remained the only representative of the line. Rome recognized him in 1783 as metropolitan bishop of Mosul and administrator of the Alqosh/Mosul patriarchate. Only in 1830, after the death in 1827 of Augustine Hindi, the representative of the Josephite line, who had also been under consideration for recognition as the Catholic patriarch, was he acknowledged by Rome as patriarch.