Author
- Hugh of Saint-Cher1
- Ibn Bardis1
- Ibn Battal1
- Ibn Luyun1
- Ibn Malik1
- Ibn Manzur1
- Ibn Qudamah1
- Ibn al-Kharrāṭ1
- Ibn al-Ḥājib1
- Innocent IV1
- Innocent V1
- Isaac Alfasi1
- Ismail al-Isfahani1
- Izz al-Din ibn Hibatullah ibn Abi l-Hadid1
- Jacob HaLevi of Marvège1
- Jacobus de Burgo1
- Jacopone da Todi1
- Jalal al-Din al-Qazwini1
- James of Lausanne1
- James of Viterbo1