- Jewish religious poetry, Hebrew4
- Jewish travelers1
- Jews26
- Jews--Dietary laws1
- Jews--Medicine4
- Jews--Persecutions1
- Jiménez de Cisneros, Francisco, 1436?-15171
- Jiménez de Enciso family1
- Jiménez de Enciso, Andrés1
- Jiménez de Enciso, Diego1
- Jiménez de Enciso, Pedro1
- Joachim, Saint1
- John Chrysostom, Saint, -40718
- John I, King of Portugal, 1357-14331
- John II, King of Aragon, 1397-14791
- John IV, King of Portugal, 1604-16561
- John Manuel, Prince of Portugal, 1537-15541
- John V, King of Portugal, 1689-17501
- John VIII Palaeologus, Emperor of the East, 1392-14481
- Joseph (Son of Jacob)1