- Art, Flemish1
- Arte della lana (Guild : Florence, Italy)1
- Artedo, Petrus de1
- Artillery1
- Artisans--Taxation1
- Asceticism--Early church1
- Asia1
- Astrology, Iranian1
- Astrology, Roman1
- Astrometeorology1
- Astronomy--Tables1
- Atlantic Ocean--English Channel1
- Atlases (Geographic)1
- Attila, -4531
- Augustus, Emperor of Rome, 63 B.C.-14 A.D.1
- Aurispa, Giovanni, approximately 1376-14591
- Austria--Lower Austria1
- Autos-da-fé1
- Averroës, 1126-1198. Talkhīs kitāb al-ʻIbārah1
- Averroës, 1126-1198. Talkhīṣ kitāb al-maqūlāt1