- James, the Greater, Saint1
- Jamʻ al-jawāmiʻ fī al-uṣūl (Subkī, Tāj al-Dīn ʻAbd al-Wahhāb ibn ʻAlī)1
- Japanese poetry1
- Javanese language1
- Jerónima de la Asunción, madre, 1555-16301
- Jesuit drama, Spanish1
- Jewish ethics1
- Jewish illumination of books and manuscripts1
- Jews--Dietary laws1
- Jews--Education1
- Jews--Legal status, laws, etc.1
- Jiménez de Cisneros, Francisco, 1436?-15171
- 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 the Baptist's Day1
- John, Duke of Burgundy, 1371-14191
- John, King of England, 1167-12161
- Jonah (Biblical prophet)1