By 200 BCE, the Romans based their armies around the maniple (‘handful’) of c. 160 men, typically arrayed in the quincunx checkerboard formation; this supplied the flexibility to outmanoeuvre enemies arrayed in a massed phalanx, or respond to more mobile cavalry attack. In battle, the Romans usually placed patrician cavalry on the flanks, with Roman infantry in the centre, with the alae legions of allies sandwiched between. The velites acted as shock-troops, hurling their javelins at the enemy in an initial assault, then withdrawing through the ranks. The heavy infantry, the hastati and principes, bore the brunt of the fighting. Triarii, the most experienced troops, held the rear, fighting last-ditch defences and turning close-matched encounters. Each maniple had two centurions, a standard-bearer and trumpeter (critical for conveying battle instructions above the din of combat). Soldiers were levies: near continual war resulted in mounting social tensions, necessitating the professionalizing Marian reforms from 107 BCE.
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