Leontius the Mechanic (Λεόντιος ὁ Μηχανικός) was a technical author of the 5th–6th century CE. His existence is known only from his sole surviving treatise, which identifies him as a μηχανικός—a practitioner of engineering, architecture, or military mechanics [1]. His work reflects the continuity of Hellenistic and Roman engineering traditions into the early Byzantine period.

His only known work is the Poliorketika (Πολιορκητικά, "On Siegecraft"), a treatise on siege engines and artillery [1].

Leontius is significant as a representative of the practical literature that transmitted ancient mechanical knowledge. His Poliorketika forms part of the tradition of military manuals and serves as a witness to the state of military technology and applied engineering practice during Late Antiquity [1].

Sources 1. Perseus Digital Library (Tufts University): https://www.perseus.tufts.edu/hopper/text?doc=Perseus:text:1999.04.0057:entry=leonti/us