Author
- Jacobus de Cessolis1
- Jacobus de Voragine1
- Jacques Legrand1
- Jalaluddin al-Mahalli1
- Jean de Meun1
- Johannes Gherinx1
- John Cassian1
- John Lydgate1
- John of Glastonbury1
- John of Howden1
- Juan Antonio de Hozes Sarmiento1
- Juan Ortiz Campoy1
- Julian of Toledo1
- Kamal Khujandi1
- Khaqani1
- Khushal Khan Khattak1
- Khwaja Abdullah Ansari1
- Kirmānī, Muḥammad ibn ʻAlī1
- Leon Battista Alberti1
- Leonardo Mainardi1