- Jews--Medicine1
- Jews--Persecutions5
- Ji bu--Bie ji lei--Ming21
- Ji bu--Bie ji lei--Yuan1
- Ji bu--Zong ji lei--Cong bian1
- Jighmīnī, Maḥmūd ibn Muḥammad, -1221? Mulakhkhaṣ fī al-hayʼah1
- Jihad1
- John I, King of Portugal, 1357-14331
- John VIII Palaeologus, Emperor of the East, 1392-14481
- John the Baptist's Day1
- Joseph (Son of Jacob)2
- Joseph Della Reina, active 15th century1
- Juana, of Austria, Princess of Portugal, 1535-15731
- Judaism12
- Judaism--Customs and practices4
- Judaism--Liturgy4
- Judaism--Prayers and devotions2
- Judeo-Arabic language2
- Judeo-Arabic literature8
- Judgment Day (Islam)1