- González, Fernán, conde de Castilla, -9701
- Great Britain1
- Gregorian chants1
- Guzman family1
- Guzman, Alfonso Perez de, 1256-13091
- Henry I, King of Castile, 1204-12171
- Henry II, King of Castile, 1333-13791
- Henry III, King of Castile and León, 1379-14061
- Heraldry1
- Hermits1
- History, Ancient1
- History, Modern1
- Hymns1
- Ildephonsus, Saint, approximately 610-6671
- Illumination of books and manuscripts1
- Inheritance and succession1
- Inquisition1
- Inscriptions, Latin1
- Interfaith relations1
- Isagoge (Porphyry)1