- Hussites1
- Hydrostatics1
- Hypothesis1
- Ibn Ghāzī, Muḥammad ibn Aḥmad, 1437 or 1438-1513. Munyat al-ḥussāb1
- Ibn al-Nafīs, ʻAlī ibn Abī al-Ḥazm, 1210 or 1211-1288. Mūjiz1
- Ibn Ḥijjah al-Ḥamawī, Taqī al-Dīn Abū Bakr ibn ʻAlī, -1434. Badīʻīyah1
- Illegitimacy1
- Illumination of books and manuscripts, Carolingian1
- Illumination of books and manuscripts, Flemish1
- Illumination of books and manuscripts, French1
- Illumination of books and manuscripts--Technique1
- In Coena Domini bulls1
- India--Cochin1
- India--Jammu and Kashmir1
- India--Malwa (Madhya Pradesh and Rajasthan)1
- Indians, Treatment of1
- Indulgences1
- Indulgences (Canon law)1
- Infancy narratives (Gospels)1
- Inheritance and succession (Islamic law)1