- Juana, la Loca, Queen of Castile, 1479-15551
- Juana, of Austria, Princess of Portugal, 1535-15731
- Judges1
- Julius III, Pope, 1487-15551
- Jurisprudence1
- Justa, Saint, -approximately 2871
- Justice, Administration of1
- Jābir ibn Ḥayyān1
- Jāmiʻ al-Azhar1
- Jāmiʻ al-Muẓaffarī (Damascus, Syria)1
- Kanz al-daqāʼiq (Nasafī, ʻAbd Allāh ibn Aḥmad)1
- Karaite manuscripts1
- Karaitic literature1
- Kashshāf (Zamakhsharī, Maḥmūd ibn ʻUmar)1
- Kaʻbah (Mecca, Saudi Arabia)1
- Kemalpaşazade, 1468 or 1469-15341
- Kings and rulers--Religious aspects1
- Kirchmair, Georg, 1481-15541
- Land grants1
- Land value taxation1