Encyclopedias, Almanacs, Transcripts, and Maps
- Alpha, Operation
- Alsina, Adolfo (1829–1877)
- Alsina, Valentín (1802–1869)
- Alsogaray, Álvaro (1913–2005)
- Alsop, Joseph Wright, V
- Alston, William P. (1921–)
- Altaians
- Altalena
- Altamirano, Ignacio Manuel (1834–1893)
- Altar de Sacrificios
- Altays
- Altepetl
- Alterity
- Althusius, Johannes (1557–1638)
- Altun Ha
- Alur
- Alurista (1947–)
- Alva Ixtlilxochitl, Fernando (c. 1578–1650)
- Alvarado Tezozomoc, Don Hernando (c. 1525–c. 1610)
- Alvarado Xicotencatl, Leonor (1524–1583)