How was the Macedonian phalanx organized under Philip II?

Under the reign of Philip II, the Macedonian phalanx was transformed into a highly disciplined and formidable tactical unit. Key aspects of its organization included:

• Formation and Depth: The phalanx was organized into battalions of approximately 1,500 men, typically arranged 16 ranks deep (or 15 in some accounts).12
• Weaponry: The primary weapon was the sarissa, a long pike measuring between 13 and 21 feet. In battle, the first four or five ranks held their pikes horizontally, creating a dense wall of spearpoints. The remaining ranks held their pikes vertically, which provided a defensive screen and a formidable appearance.12
• Equipment: Soldiers were equipped with helmets, leather corselets, metal greaves, and small round shields.2
• Tactical Support: To address the inherent rigidity of the phalanx, Philip II integrated mobile support units. Light infantry—including archers, slingers, and javelin men—protected the flanks, while heavy cavalry was deployed to charge enemy weak points.12

This structure allowed the Macedonian army to maintain a nearly impregnable frontal defense while utilizing combined arms to achieve battlefield success.2