Author
- Isaac of Troki2
- Isfarāyīnī, Muḥammad ibn Muḥammad, d. 13462
- Jacob ben Jacob, ha-Kohen, -approximately 12702
- Jacopo Piccolomini-Ammannati2
- Jacopone da Todi2
- Jakob Reifmann2
- James of Lausanne2
- Jamāl al-Dīn Khvānsārī2
- Jamāl al-Dīn Ḥaṣīrī2
- Jarmakī, Abū Bakr ibn al-Ṭāhir, 18th cent2
- Jayāditya2
- Jean Germain2
- Joan Martines2
- Joannes Oliva2
- Johann Herolt2
- Johann Neudörffer the Elder2
- Johannes Nider2
- Johannes von Freiburg2
- John Burgh2
- John Felton2