Encyclopedias, Almanacs, Transcripts, and Maps
- Iran, Islamic Republic of
- Iran, The Catholic Church in
- Iraq, The Catholic Church in
- Irāqī, Eleazar ben Aaron Ha-Kohen°
- Irāqī, Shalom Ha-Kohen
- Irbil
- Ireland, John
- Ireland, John, Bl.
- Ireland, Seraphine, Mother
- Ireland, The Catholic Church in
- Irenaeus, St.
- Irene of Portugal, St.
- Irene, Byzantine Empress
- Irenicism
- Irgun Ẓeva'i Le'ummi
- Irish Catholic Colonization Association of the U.S.
- Irish Christian Brothers
- Irish Colleges on the Continent
- Irish Confessors and Martyrs
- Irish Crosses