Author
- Jean de Roquetaillade1
- Johannes Meyer1
- John Capgrave1
- John Cassian1
- John Cleseby1
- John Mandeville1
- John Shirley1
- John Tiptoft, 1st Earl of Worcester1
- John Wycliffe1
- John of Glastonbury1
- John of Howden1
- John of Lancaster, 1st Duke of Bedford1
- John of Wales1
- John, Duke of Berry1
- Joseph Angelet1
- Joseph ben Abraham Gikatilla1
- Josephus1
- Judah ben Saul ibn Tibbon1
- Jullien Gervais1
- Justin1