- Adventure stories, Spanish1
- Aeneas (Legendary character)1
- Aeneis (Virgil)2
- Aesthetics1
- Affinity (Law)1
- Agriculture2
- Agustín, Antonio, 1517-1586. Dialogos de medallas inscriciones y otras antiguedades1
- Ajurrūmīyah (Ibn Ājurrūm, Muḥammad ibn Muḥammad)2
- Al-Munajjim al-Kashi, Yahya ibn Imad bin Yahya1
- Alba, Fernando Alvarez de Toledo, duque de, 1507-15821
- Alchemy2
- Alexander VII, Pope, 1599-16671
- Alexander, the Great, 356 B.C.-323 B.C.1
- Alfonso I King of Asturias, 693-7561
- Alfonso III, King of Asturias and Leon, approximately 848-approximately 9101
- Alfonso V, King of Asturias and León, 994-1027 or 10281
- Alfonso VI, King of Castile and Leon, 1030-11091
- Alfonso VII, The Emperor, King of Castile, 1104-11571
- Alfonso VIII, King of Castile, 1155-12141
- Alfonso X, King of Castile and Leon, 1221-12843