Agathodaemon of Alexandria (Ἀγαθοδαίμων Ἀλεξανδρεὺς) Life Agathodaemon of Alexandria is traditionally identified as a 4th-century CE geographer or cartographer. He is known solely from later references, and no biographical details of his life or background survive [1].

Works He is credited with designing or engraving a set of world maps to illustrate Claudius Ptolemy’s 2nd-century geographical treatise, the Geography [1][2]. These maps, created posthumously to visualize Ptolemy’s coordinate data, are lost but were reconstructed in later Byzantine manuscripts.

Significance Agathodaemon’s importance stems from his legendary association with Ptolemaic cartography. Ptolemy does not mention him; his name appears in later manuscript traditions crediting him with delineating the world according to Ptolemy’s instructions [1][2]. Scholars often consider "Agathodaemon" (meaning "good spirit") a pseudonym or a name applied by copyists. Nevertheless, his name became permanently attached to the transmission and visualization of Ptolemy’s geographical system through the Medieval and Early Modern periods.

Sources 1. Encyclopædia Britannica: https://www.britannica.com/biography/Agathodaemon 2. Oxford Research Encyclopedias: https://oxfordre.com/classics/classics/view/10.1093/acrefore/9780199381135.001.0001/acrefore-9780199381135-e-204