- Jiménez de Enciso, Diego1
- Jiménez de Enciso, Pedro1
- Jinn2
- Jiří, z Poděbrad, King of Bohemia, 1420-14711
- Joannes de Caligariis1
- John, of Damascus, Saint1
- John, of Daylam1
- John, the Baptist, Saint1
- Joseph (Son of Jacob)2
- Joseph (Son of Jacob) in the Qurʼan1
- Juan II, King of Castile and Leon, 1405-14541
- Juana, la Loca, Queen of Castile, 1479-15552
- Juana, of Austria, Princess of Portugal, 1535-1573--Correspondence1
- Judaism22
- Judaism--Customs and practices16
- Judaism--Liturgy18
- Judaism--Liturgy--Texts8
- Judaism--Prayers and devotions5
- Judeo-Arabic literature4
- Judeo-Italian language1