Author
- Jayāditya1
- Jean Bayard1
- Jean Gerson1
- Jean Passerat1
- Joham de Vernoils1
- Johannes Appenzeller1
- Johannes Lichtenberger1
- Johannes Mellarinus1
- Johannes Schöner1
- Johannes Tostius1
- Johannes de Sacrobosco1
- Johannes von Kastl1
- John Cornelius1
- John Frederick II of Saxony1
- John II of Castile1
- John XXI1
- John of Ibelin1
- John Dokeianos1
- Joseph ben Ephraim Karo1
- Joseph ben Moses Sarfati1