The roman legion vs the Greek Phalanx The Roman legion and the Greek phalanx were two dominant military formations in ancient warfare, each with distinct strategies and structures. The Greek phalanx, especially prominent in the 5th to 4th centuries BCE, consisted of heavily armed infantry (hoplites) arranged in a tight, rectangular formation. Soldiers relied on each other for protection, using long spears (sarissas) and large shields (hoplons) to create a wall of spear tips. While effective for