- Innocent III, Pope, 1160 or 1161-12161
- Irshād al-adhhān ilá aḥkām al-īmān (Ibn al-Muṭahhar al-Ḥillī, al-Ḥasan ibn Yūsuf)1
- Isabel, of Coimbra, Queen, consort of Afonso V, King of Portugal, 1432-14551
- Isagoge (Porphyry)1
- Isaiah (Biblical prophet)1
- Isfarāyīnī, Muḥammad ibn Muḥammad, -1285. al-Lubāb fī ʻilm al-iʻrāb1
- Islam1
- Islam--Customs and practices1
- Islamic countries1
- Italian literature--Societies, etc.1
- Italy--Genoa1
- Italy--Rome1
- Italy--Siena1
- James IV, King of Scotland, 1473-15131
- Jaunaye, Etienne Chaton, sieur de, 1543-1
- Jaymes, Diego1
- Jerome, Saint, -419 or 4201
- Jewelled bindings1
- Jewelry1
- Jewish philosophy1