The way the battles were fought showed why the army became so powerful. The main force advanced in three lines, consisting of the Hastati, Principes, and Triarii, in that order. The Velites formed a light screen in front. Though it is unclear the exact formation the army took, it is generally agreed that the maniples (units of 120 men) were arranged in a checkerboard formation, so the first line could fall back if need through the lines of the second without breaking up formation. As the enemy approached, the Velites would pepper the enemy with javelin fire until the depleted their ammunition or else the charging enemy got too close, and then they would retreat through the lines of the Hastati and on to the back of the army. When the enemy came within thirty or so yards, the Hastati would release a volley of their pila, to further weaken the lines and the morale of the enemy. When the fighting became hot, and the first line Hastati become tired or incur too many losses, they would fall back through the Principes, in which case they would pick up the fight with renewed strength. If they continued to fight and lose ground, then the Principes would fall back through the line of Triarii, which were the last line of defense. They then would present the enemy with a line of heavy spears and fresh strength, which would hopefully be enough to win the battle. As the Roman saying went, “It has come to the Triarii”, meant that the battle had progressed to the bitter end, and was possible the turning point.
As the Roman Republic expanded and spilt blood, so did the power of the army and the effect it had on society. During this time of aggressive expansion, economic benefits constantly strengthened the empire, and the army’s achievements continued to bring glory to militaristic culture of Rome.