| 280 |
Diocese of Perat-Maishan (Chaldean Rite) was established |
| 300 |
Archdiocese of Kaškar (Chaldean Rite) was established |
| 300 |
Diocese of Seleucia–Ctesifonte (Chaldean Rite) was established |
| 400 |
Diocese of Seleucia–Ctesifonte (Chaldean Rite) was promoted as Metropolitan Archdiocese of Seleucia–Ctesifonte |
| 410 |
Diocese of Perat-Maishan (Chaldean Rite) was promoted as Metropolitan Archdiocese of Perat-Maishan |
| 500 |
Archdiocese of Kaškar (Chaldean Rite) was suppressed |
| 800 |
Metropolitan Archdiocese of Babylon (Chaldean Rite) was established (from the suppressed Metropolitan Archdiocese of Seleucia–Ctesifonte) |
| 800 |
Metropolitan Archdiocese of Seleucia–Ctesifonte (Chaldean Rite) was suppressed (to establish Metropolitan Archdiocese of Babylon) |
| 1200 |
Metropolitan Archdiocese of Perat-Maishan (Chaldean Rite) was suppressed |
| 1553.04.20 |
Metropolitan Archdiocese of Babylon (Chaldean Rite) was promoted as Patriarchal See of Babylon |
| 1553.04.20 |
Metropolitan Archdiocese of Baghdad (Chaldean Rite) was established |
| 1628 |
Mission sui juris of Syria and Cilicia was established |
| 1632.09.06 |
Diocese of Baghdad was established (without ecclesiastical province) |
| 1750 |
Mission sui juris of Mossul was established |
| 1785 |
Diocese of Amadiyah (Chaldean Rite) was established (became suffragan of Babylon) |
| 1789 |
Metropolitan Archdiocese of Kirkuk (Chaldean Rite) was established |
| 1790 |
Archdiocese of Mossul (Syriac Rite) was established (without ecclesiastical province) |
| 1800 |
Diocese of Mossul (Chaldean Rite) was established (without ecclesiastical province) |
| 1817 |
Mission sui juris of Syria and Cilicia was promoted as Apostolic Prefecture of Syria and Cilicia |
| 1838.09.17 |
Patriarchal Exarchate of Iraq (Greek-Melkite Rite) was established |
| 1848.08.19 |
Diocese of Baghdad was promoted as Archdiocese of Baghdad |
| 1850 |
Diocese of Aqrā (Chaldean Rite) was established (from Diocese of Amadiyah) |
| 1850 |
Diocese of Zaku (Chaldean Rite) was established (from Diocese of Amadiyah and Diocese of Gazireh) |
| 1860 |
Titular Archiepiscopal See of Perat-Maishan (Chaldean Rite) was restored |
| 1862.09.28 |
Archdiocese of Baghdad (Syriac Rite) was established (without ecclesiastical province) |
| 1895 |
Titular Archiepiscopal See of Perat-Maishan (Chaldean Rite) was suppressed |
| 1895.04.23 |
Diocese of Aqrā (Chaldean Rite) was suppressed (to Diocese of Amadiyah) |
| 1896 |
Apostolic Prefecture of Syria and Cilicia was demoted as Mission sui juris of Syria and Cilicia |
| 1910.02.24 |
Diocese of Aqrā (Chaldean Rite) was restored (from Diocese of Amadiyah and became suffragan of Babylon) |
| 1953 |
Mission sui juris of Syria and Cilicia was suppressed |
| 1954.01.17 |
Archdiocese of Bassorah (Chaldean Rite) was restored (from Metropolitan Archdiocese of Baghdad and without ecclesiastical province) |
| 1954.06.29 |
Archdiocese of Baghdad (Armenian Rite) was established (from Archdiocese of Mardin and without ecclesiastical province) |
| 1960.10.24 |
Diocese of Alquoch (Chaldean Rite) was established (from Metropolitan Archdiocese of Baghdad and became suffragan of Babylon) |
| 1967 |
Titular Archiepiscopal See of Kaškar (Chaldean Rite) was restored |
| 1967.02.14 |
Diocese of Mossul (Chaldean Rite) was promoted as Archdiocese of Mossul |
| 1968.03.07 |
Archdiocese of Erbil (Chaldean Rite) was established (from Metropolitan Archdiocese of Kirkuk and without ecclesiastical province) |
| 1968.03.07 |
Diocese of Sulaimaniya (Chaldean Rite) was established (became suffragan of Kirkuk) |
| 1969 |
Mission sui juris of Mossul was suppressed |
| 1980 |
Titular Episcopal See of Anbar (Chaldean Rite) was established |
| 1986 |
Titular Metropolitan See of Tagritum (Syriac Rite) was established |
| 1991 |
Patriarchal Exarchate of Basra and the Gulf (Syriac Rite) was established |
| 2004.07 |
Titular Episcopal See of Hirta was established |
| 2013.06.10 |
Diocese of Amadiyah (Chaldean Rite) was renamed as Diocese of Amadiyah and Zaku (gained territory from the suppressed Diocese of Zaku) |
| 2013.06.10 |
Diocese of Zaku (Chaldean Rite) was suppressed (to Diocese of Amadiyah and Zaku) |
| 2013.07.11 |
Metropolitan Archdiocese of Kirkuk (Chaldean Rite) was renamed as Metropolitan Archdiocese of Kirkuk–Sulaimaniya (gained territory from the suppressed Diocese of Sulaimaniya and lost suffragan see Sulaimaniya) |
| 2013.07.11 |
Diocese of Sulaimaniya (Chaldean Rite) was suppressed (to Metropolitan Archdiocese of Kirkuk–Sulaimaniya) |
| 2018.12.22 |
Diocese of Aqrā (Chaldean Rite) was suppressed (to Archdiocese of Mossul–Aqrā) |
| 2018.12.22 |
Archdiocese of Mossul (Chaldean Rite) was renamed as Archdiocese of Mossul–Aqrā (gained territory from the suppressed Diocese of Aqrā) |
| 2019.06.28 |
Diocese of Adiabene (Syriac Rite) was established (from Archdiocese of Mossul and without ecclesiastical province) |
| 2020.06.27 |
Diocese of Amadiyah and Zaku (Chaldean Rite) was renamed as Diocese of Duhok (lost territory to establish Diocese of Zakho) |
| 2020.06.27 |
Diocese of Zakho (Chaldean Rite) was restored (from Diocese of Amadiyah and Zaku and became suffragan of Babylon) |
| 2020.09.10 |
Titular Metropolitan See of Tagritum (Syriac Rite) was demoted as Titular Episcopal See of Tagritum |
| 2022.02.19 |
Patriarchal See of Babylon (Chaldean Rite) was renamed as Patriarchal See of Baghdad |
