Author
- Joseph ben Moses Sarfati1
- Juan de Torquemada1
- Juana I of Castile1
- Judah ben Saul ibn Tibbon1
- Julianus Pomerius1
- Jullien Gervais1
- Junayd ibn Sandal Baghdādī1
- Justin1
- Jörg Muelich1
- Kalonymus ben Kalonymus1
- Khaṭīb Qādā, ʻAbd Allāh ibn Muḥammad, active 15th century1
- Kingdom of England1
- Kingdom of Naples1
- Klaus von Stille1
- Konrad III. von Soltau1
- Laurentius Cynthius1
- Leo Archpriest1
- Leo I1
- Lope de Espejo1
- Lope de Olmedo1