Author
- Humbert of Romans1
- Iachetus Italianus1
- Iacopo Bracciolini1
- Iacopo da Benevento1
- Ibn Daqiq al-Eid1
- Ibn Ghānim, ʻIzz al-Dīn ʻAbd al-Salām ibn Aḥmad, -1279?1
- Ibn Malik1
- Ibn al-Kharrāṭ1
- Ibrāhīm al-Ḥusaynī1
- Ibrāhīm ibn Aḥmad ʻAsqalānī1
- Ibrāhīm ibn ʻAbd Allāh Qīrāṭī1
- Innocent VIII1
- Isidore of Seville1
- Iskandar Rūmī1
- Ismāʻīl ibn Abī Bakr Ibn al-Muqrī1
- Jacob ben Jacob, ha-Kohen, -approximately 12701
- Jacobus Balbi1
- Jacobus de Teramo1
- Jacopo Nannis de Piccolomini1
- Jacopo Piccolomini-Ammannati1