- Abbazia di S. Maria di Porcilia (Padua, Italy)1
- Abbazia di Santa Giustina (Padua, Italy)1
- Abbazia di Santo Stefano (Pistoia, Italy)1
- Abbots1
- Absalom (Biblical figure)1
- Absolution1
- Acciaioli, Antonio1
- Acciaioli, Francesco1
- Accursius, glossator, approximately 1182-approximately 12601
- Acrostics1
- Actions and defenses1
- Adrian VI, Pope, 1459-15231
- Aegidius, Saint, Abbot1
- Aeneis (Virgil)1
- Affinity (Law)1
- Agazaria, Claudio Boncompagni di1
- Agnes, Saint, Martyr1
- Agreda, Dominici d'1
- Alban, Saint, -304?1
- Albertus de Fontanella1