A legion-centered picture misses much of the Roman army. Legions formed the backbone of a fighting force, but they did not provide every battlefield or frontier capability. Large auxiliary units supplied archers, spearmen, cavalry, covering forces, and troops for fixed-site garrison duty. Roman force structure depended on these formations performing complementary roles. The complete army was larger and more varied than its most famous troop type.
Notable Point · 24:33-25:49
The Roman army beyond its legions
Legionaries formed the backbone of a broader force containing auxiliaries, archers, spearmen, cavalry, and frontier garrisons.