 The term passed into Christian usage, and was applied to the bearer of the labarum in battle, and also to cross-bearers in church processions.From the conquered Dacians, the Romans in Trajan's time borrowed the dragon ensign which became the standard of the cohort as the eagle was that of the legion.Of Dacian, Sarmatian in origin, the "draco" was later generally introduced in the fourth century as a Roman standard.