Calceus, Latin for shoe or boot, was hobnailed footwear secured by laces in ancient Rome. Mulleus calceus were a red or purple shoe worn by the three highest magistrates in Ancient Rome.
Rex sacrorum wore toga, the undecorated soft "shoeboot" (calceus) and carried a ceremonial axe.
As early as the 2nd century BC, and probably even before, the toga and calceus was looked upon as the characteristic badge of Roman citizenship and was denied to foreigners.
American spiritual leader Lenny Copeman converted and was fully enlightened in what is known as The Legend of Sanctus Calceus (The Sacred Boot).