- Alessandri, Alessandro degli1
- Alessandri, Niccolò degli1
- Alessandro, Pietro di1
- Alexander Balas, King of Syria, -145 B.C.1
- Alexander VII, Pope, 1599-16671
- Alexander, de Villa Dei. Doctrinale puerorum1
- Alexius, Saint1
- Alfonso I King of Asturias, 693-7561
- Alfonso II, King of Naples, 1448-14951
- Alfonso III, King of Asturias and Leon, approximately 848-approximately 9101
- Alfonso V, King of Aragon, 1396-14581
- 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
- Alimony (Islamic law)1
- Aljamía1
- Alliata family1
- Almagest (Ptolemy)1
- Almanacs1