Its main function was to intervene in cases of popular revolts. It was “the Praetorian Guard.” Initially consisted of 500 men, but in later years the number increased to one thousand. They were armed with a large shield and a sword called gladium small, and had called turmas riders squads.
Sometimes Praetorians joined the protests of the people and turned against their superiors, as happened in AD 41. C., when Caligula killed.