Celeres

The Celeres were a personal armed guard of 300-500 men maintained by Romulus, the mythical founder of ancient Rome. The Celeres were associated with Celer, the lieutenant of Romulus responsible for Remus' slaying in some stories. Livy mentions that they served in peacetime and in war, unlike the short terms of service in most ancient armies (including Rome's). It is unknown whether they were infantry or cavalry; Dionysius claims the former, while Livy and other sources argue that the Celeres were a cavalry unit. The latter seems more plausible given that celeres means literally "the swift".