Author
- Innocent IV1
- Isaac Israeli ben Solomon1
- Isaac ben Joseph of Corbeil1
- Isidore of Seville1
- Ismail ibn Hammad al-Jawhari1
- Ivo of Chartres1
- Jacopo Piccolomini-Ammannati1
- Jacques Lempereur1
- Jaghmini1
- Jean Carteron1
- Johannes von Kastl1
- John Burgh1
- John of Lancaster, 1st Duke of Bedford1
- Josephus1
- Kingdom of England1
- Laurent d'Orleans1
- Magister Contarinus1
- Marceiu Vinnen1
- Martin of Opava1
- Matteo Piccolomini1