Legio I Isaura Sagittaria: one of the legions of the later Roman empire. Its name means "the first Isaurian legion of archers".
This legion is mentioned in the late-antique text known as Notitia Dignitatum as one of the units belonging to the field army that was stationed in the east. The name suggests that the legion was founded to garrison a region, Isauria in the Taurus mountain range, and that it was later added to the field army. Its creator must have been the emperor Probus (276-282), who is known to have campaigned against the mountain tribes of Cilicia.
The name sagittaria suggets that the soldiers were also used to fighting as archers, which was not common among legionaries, but must have been useful during the legion's stay in Isauria.