▁Gener als ▁with ▁imper ium ▁( the ▁right ▁to ▁command ▁an ▁army ) ▁were ▁magistr ates ▁or ▁prom ag istr ates , ▁accompanied ▁at ▁all ▁times ▁by ▁their ▁l ict ors , ▁who ▁would ▁act ▁as ▁close ▁protection . ▁Cons uls ▁and ▁pro cons uls ▁had ▁twelve ▁l ict ors , ▁whilst ▁pra et ors ▁and ▁prop ra et ors ▁had ▁six ; ▁enough ▁to ▁guard ▁the ▁general ' s ▁tent ▁in ▁camp , ▁but ▁too ▁few ▁to ▁be ▁effective ▁as ▁a ▁body guard ▁in ▁battle . ▁There ▁was ▁no ▁permanent ▁body guard ▁formation , ▁so ▁some ▁military ▁officers ▁began ▁to ▁surr ound ▁themselves ▁with ▁temporary ▁units ▁of ▁hand - p icked ▁soldiers ▁to ▁ensure ▁their ▁security ▁during ▁battle . ▁For ▁example , ▁during ▁the ▁Sie ge ▁of ▁Num ant ia , ▁Sci pio ▁A em ilian us ▁formed ▁a ▁tro op ▁of ▁ 5 0 0 ▁men ▁to ▁protect ▁himself ▁against ▁sort ies , ▁which ▁were ▁often ▁directed ▁at ▁command ers . ▁This ▁practice ▁become ▁more ▁w ides p read ▁in ▁the ▁army ▁of ▁the ▁late ▁Republic , ▁as ▁gener als ▁remained ▁on ▁campaign ▁for ▁longer ▁periods . ▁In ▁camp , ▁the ▁body guard ▁would ▁sleep ▁close ▁to ▁the ▁commander , ▁whose ▁tent ▁was ▁known ▁as ▁the ▁pra et or ium . ▁According ly , ▁the ▁picked ▁guard ▁became ▁known ▁as ▁coh ors ▁pra et oria . ▁In ▁battle , ▁these ▁coh ort s ▁would ▁act ▁as ▁a ▁final ▁reserve . ▁ ▁At ▁the ▁end ▁of ▁the ▁year ▁ 4 0 ▁BC