Author
- Hippocrates1
- Holy Roman Empire1
- House of Requesens1
- House of Ventimiglia1
- House of della Rovere1
- Hugh Bigod, 3rd Earl of Norfolk1
- Hugh Talemache1
- Hugo Trottus1
- Iachetus Italianus1
- Iacopo da Benevento1
- Ildibrandinus1
- Isaac Israeli ben Solomon1
- Isaac Newton1
- Jacobo Bellenden1
- Jacobus Balbi1
- Jacobus Dinetus1
- Jacobus de Burgo1
- Jacopo Nannis de Piccolomini1
- Jacopo Ragone1
- Jacopone da Todi1