- Italy--Terranuova Bracciolini1
- Italy--Torri in Val di Pesa3
- Italy--Venice5
- Italy--Vercelli (Province)1
- Italy--Vernio1
- Italy--Vicopisano1
- Iʻrāb ʻan qawāʻid al-iʻrāb (Ibn Hishām, ʻAbd Allāh ibn Yūsuf)1
- Iḥyāʼ ʻulūm al-dīn (Ghazzālī)1
- Iṣfahānī, Maḥmūd ibn ʻAbd al-Raḥmān, 1275 or 1276-1348 or 1349. Tasdīd al-ʻaqāʼid fī sharḥ Tajrīd al-qawāʻid2
- Jacopo, Bernardo di1
- Jacopo, Giovanni di1
- Jaghmīnī, Maḥmūd ibn Muḥammad, -1221?1
- Jamʻ al-jawāmiʻ fī al-uṣūl (Subkī, Tāj al-Dīn ʻAbd al-Wahhāb ibn ʻAlī)2
- Japan1
- Jaʻbarī, Ṣāliḥ ibn Thāmir, d. 1306. Naẓm al-laʼālī2
- Jean, de Verdun1
- Jerome, Saint, -419 or 4202
- Jesus Christ28
- Jewish (culture or style)1
- Jewish astronomy5