- Gregorian chants--Instruction and study1
- Gregory IX, Pope, approximately 1170-12411
- Gregory XIII, Pope, 1502-15851
- Gregory XV, Pope, 1554-16231
- Griselda (Legendary character)1
- Guatemala1
- Guglielmo, da Varignana, approximately 1270-13391
- Guido, d'Arezzo1
- Guilds1
- Gunnery1
- Gunpowder1
- Guy of Warwick (Legendary character)--Romances1
- Guzman family1
- Guzman, Alfonso Perez de, 1256-13091
- Gynecology1
- Hadith (Shiites)--Authorities1
- Hadith--Abrogator and abrogated Hadith1
- Hadith--Commentaries1
- Hadith--Prophecies1
- Hadrian, Emperor of Rome, 76-1381