 Additionally, the Emperor Gallienus took the revolutionary step of forming an entirely cavalry field army, which was kept as a mobile reserve at the city of Milan in northern Italy.It is believed that Gallienus facilitated this concentration of cavalry by stripping the legions of their integral mounted element.A diverse range of cavalry regiments existed, including "catafractarii" or "clibanarii", "scutarii", and legionary cavalry known as "promoti".