- Gregory I, Pope, approximately 540-6042
- Gregory IX, Pope, approximately 1170-12411
- Gregory XIII, Pope, 1502-15853
- Gregory, of Nazianzus, Saint2
- Grossa, Dora active 16th century1
- Guasconi, Pierantonio1
- Guelfs and Ghibellines1
- Guido, d'Arezzo1
- Hadrian, Emperor of Rome, 76-1381
- Haggadah5
- Haggadot1
- Hagiographies2
- Hagiography2
- Hagiography in literature2
- Halakhot (Alfasi, Isaac ben Jacob)1
- Half bindings5
- Handbooks and manuals6
- Hannibal, 247 B.C.-182 B.C.1
- Hanukkah--Liturgy1
- Harmonics (Ptolemy)1