Belisarius's 25,000-man army may have been roughly one-third cavalry, while much of its infantry had spent more time on garrison and policing duties than in battle. The commander's distrust of foot soldiers made mounted troops central to his plans. His force included 1,200 Hun horse archers and 300 Heruls, whose ferocity and later battlefield performance receive particular attention. Belisarius also maintained bucellarii, household cavalry named from the hard biscuit issued to soldiers and supported at his personal expense. These heavily equipped riders carried both lance and composite bow, giving the Roman army a flexible core trained to a high standard.
Chapter · 12:16-13:38
Belisarius combines Huns, Heruls, and household cavalry
The Roman army at Dara relies on experienced mounted specialists and Belisarius's bucellarii because much of its garrison-trained infantry has seen little active fighting.