- Ibn al-Nafīs, ʻAlī ibn Abī al-Ḥazm, 1210 or 1211-1288. Mūjiz al-Qānūn1
- Ibn al-ʻImād al-Aqfahsī, Aḥmad, approximately 1349-1405. Manẓūmah fī al-najāsāt al-maʻfū ʻanhā1
- Iceland1
- Incarnation1
- India1
- Indulgences2
- Inglis, Esther, 1571-16241
- Inheritance and succession (Islamic law)3
- Innocent III, Pope, 1160 or 1161-12161
- Intellectual life1
- Interfaith relations1
- International relations3
- Iran1
- Ireland1
- 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
- Islam8