Author
- John Gage1
- John Gower1
- John Halgren of Abbeville1
- John Herd1
- John XXII1
- John of Howden1
- John of Saxony1
- Josephus1
- Juan Gallo1
- Juan Martínez Silíceo1
- Juana I of Castile1
- Juvenal1
- Konrad III. von Soltau1
- Lactantius1
- Leo III1
- Leontios of Neapolis1
- Lope de Espejo1
- Lorenzo Bonincontri1
- Lucian of Samosata1
- Lucius Annaeus Florus1