- John II, King of Aragon, 1397-14791
- Julian, of Eclanum, Bishop, 380-approximately 4551
- Jumʻah1
- Jurjānī, ʻAlī ibn Muḥammad, al-Sayyid al-Sharīf, 1340-14131
- Justa, Saint, -approximately 2871
- Jāmiʻ al-ṣaḥīḥ (Bukhārī, Muḥammad ibn Ismāʻīl)1
- Jāmī, 1414-14921
- Kemalpaşazade, 1468 or 1469-1534. Risālah fī al-haykal al-insānī1
- Khamrīyah (Ibn al-Fāriḍ, ʻUmar ibn ʻAlī)1
- Kyi︠e︡vo-Pechersʹka lavra1
- Language and languages--Philosophy1
- Latin poetry1
- Laylat al-Qadr1
- Leather bindings1
- Leather doublures1
- Lebanon--Tripoli1
- Legacies (Islamic law)1
- Leocadia, Saint, -3031
- Lettering pieces1
- Limp bindings1