Author
- John XXI1
- John de Breton1
- John de Seccheville1
- John of Damascus1
- John of Garland1
- John of Howden1
- John of Saxony1
- John of Seville ?1
- Juan Luis Vives1
- Juan Martínez Silíceo1
- Jörg Muelich1
- Kingdom of England1
- Kollegium Sankt Nikolaus1
- Lambert le Bègue1
- Lapo da Castiglionchio1
- Laurentius Cynthius1
- Leonardo Loredan1
- Leonhard Freisleben1
- Leontios of Neapolis1
- Leopold Camp1