, ▁the ▁tri um vir s ▁Oct av ian ▁and ▁Mark ▁Anton y ▁both ▁operated ▁pra et or ian ▁units ▁of ▁hand - p icked ▁veter ans . ▁Oct av ian ▁g arrison ed ▁his ▁pra et ori ans ▁within ▁the ▁sacred ▁boundary ▁of ▁Rome , ▁the ▁first ▁time ▁troops ▁had ▁been ▁perman ently ▁station ed ▁in ▁the ▁city . ▁Anton y ▁commanded ▁three ▁coh ort s ▁in ▁the ▁Orient ▁and ▁in ▁ 3 2 ▁BC , ▁he ▁issued ▁co ins ▁in ▁honor ▁of ▁his ▁pra et ori ans . ▁According ▁to ▁Paul ▁O rose , ▁Oct av ian ▁commanded ▁five ▁coh ort s ▁at ▁the ▁Battle ▁of ▁Act ium . ▁Following ▁his ▁victory ▁at ▁Act ium , ▁Oct av ian ▁merged ▁his ▁forces ▁with ▁those ▁of ▁his ▁advers ary ▁in ▁a ▁symbol ic ▁reun ification . ▁When ▁Oct av ian ▁became ▁August us , ▁the ▁first ▁Roman ▁em peror , ▁he ▁retained ▁the ▁pra et ori ans ▁as ▁his ▁personal ▁body guard ▁force . ▁ ▁Under ▁the ▁emp ire ▁▁ ▁The ▁leg ion aries ▁known ▁as ▁the ▁Pra et or ian ▁Guard ▁were ▁first ▁hand - p icked ▁veter ans ▁of ▁the ▁Roman ▁army ▁who ▁served ▁as ▁body gu ards ▁to ▁the ▁em peror . ▁First ▁established ▁by ▁August us , ▁members ▁of ▁the ▁Guard ▁accompanied ▁him ▁on ▁active ▁campaign ▁and ▁served ▁as ▁secret ▁police ▁protect ing ▁the ▁civ ic ▁administr ations ▁and ▁rule ▁of ▁law ▁im posed ▁by ▁the ▁sen ate ▁and ▁the ▁em peror . ▁The ▁Pra et or ian