Roman Battle Formations

• The Roman Army used Seven Formations in Battle according to Vegetius (5th cent CE), who was quoting Frontinus (35-c.104 CE).

Vegetius’ Seven Battle Formations

1. The First Formation:
   • The oblong square.
     • Requires flat ground for the Line not to be broken.
     • Care must be taken to prevent the Enemy using any advantage of terrain to break up the Line. A larger Enemy army must be prevented from surrounding and separating both Wings.
2. The Second Formation:
   • The Oblique.
     • Right Wing advances on the Enemy Left, Left Wing holds back.
3. The Third Formation:
   • The Oblique (similar to 2)
     • Left Wing advances on the Enemy (but only if Enemy’s Right Wing is weak). Right Wing and Centre holds back. Take care not to let the line be broken by Wedges of the Enemy.
4. The Fourth Formation:
   • Right Wing and Left Wing attack simultaneously
   • (Leaves the Centre at risk).
5. The Fifth Formation:
   • (Similar to 4)
   • First, the Light Infantry and Archers form up in front of the Centre.
   • Then Right and Left Wings attack simultaneously.
   • (Centre no longer at risk).
6. The Sixth Formation:
   • The Right Wing attacks the Enemy’s Left (similar to 2), supported by the best Cavalry and Infantry.
   • The Centre and Left hold back. This produces a straight line.
   • Used on the March.
7. The Seventh Formation:
   • If the Army is inferior in numbers to the Enemy, cover one flank with a River, Sea, City or similar unapproachable Obstacle, and secure it with all the Cavalry and light troops.
   • The remaining army is formed up in a straight line.

N.B.

1. Note that whichever Wing is used for the attack, or if Wedge Formations are used to penetrate the Enemy line, they must be formed of the best and most disciplined men. Victories, in general, are won by small groups of men.
2. An escape route for the Enemy should not be blocked, as a fleeing army is easier to destroy.
3. If forced to Retreat, it should always be presented to the men as a subterfuge to entice the Enemy. The Cavalry should be used as a screen whilst withdrawing or retreat under the cover of nightfall.