For food Vegetius lists as staple corn, wine, vinegar and salt in plenty at all times. The men mostly ate porridge, bread and beans, supplemented by other vegetables and eggs, with meat on the numerous feast days, plus any obtained by hunting.
When campaigning they ate hardtack, long lasting wholewheat biscuits. Such hardships were made more acceptable by the way many generals even those of the imperial family such as Tiberius or Julian, shared their troops hardships while on campaign, sleeping on the ground and eating basic rations.