(Click on the column title to sort by that column)
| # | Catholics | Population | Percent Catholic | Diocese | Year | Source |
|---|---|---|---|---|---|---|
| 1 | 150,000 | 3,500,000 | 4.29% | Babylon {Babilonia} (Chaldean) (Archdiocese) | 1970 | ap1971 |
| 2 | 130,000 | Baghdad (Chaldean) (Archdiocese) | 2004 | ap2005 | ||
| 3 | 35,000 | Mossul (Syrian) (Archeparchy) | 2004 | ap2005 | ||
| 4 | 25,000 | Baghdad (Syrian) (Archeparchy) | 2004 | ap2005 | ||
| 5 | 20,600 | Mossul (Chaldean) (Archeparchy) | 2004 | ap2005 | ||
| 6 | 17,487 | Alquoch (Chaldean) | 2004 | ap2005 | ||
| 7 | 12,700 | Zaku (Chaldean) | 2004 | ap2005 | ||
| 8 | 12,200 | Arbil {Erbil} (Chaldean) (Archeparchy) | 2004 | ap2005 | ||
| 9 | 5,700 | Kerkuk (Chaldean) (Archdiocese) | 2004 | ap2005 | ||
| 10 | 2,500 | Bassorah (Chaldean) (Archeparchy) | 2004 | ap2005 | ||
| 11 | 2,000 | Amadiyah (Chaldean) | 2004 | ap2005 | ||
| 12 | 2,000 | Baghdad (Archdiocese) | 2004 | ap2005 | ||
| 13 | 2,000 | Baghdad (Armenian) (Archeparchy) | 2004 | ap2005 | ||
| 14 | 310 | Aqra {Akra} (Chaldean) | 2004 | ap2005 | ||
| 15 | 200 | Sulaimaniya (Chaldean) | 2004 | ap2005 |
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