Macedonian phalanx The Macedonian phalanx is an infantry formation developed by Philip II and used by his son Alexander the Great to conquer the Persian Empire and other armies . Phalanx es remained dominant on battlefields throughout the Hellenistic period , although wars had developed into more protracted operations generally involving siege s and naval combat as much as field battle s , until they were finally displaced by the Roman legions . Development . Philip II spent much of his youth as a hostage at Thebes , where he studied under the renowned general Epaminondas , whose reforms were the basis for the phalanx . Phalangites were professional soldiers , and were among the first troops ever to be drilled , thereby allowing them to execute complex maneuvers well beyond the reach of most other armies . They fought packed in a close rectangular formation , typically eight men deep , with a leader at the head of each column and a secondary leader in the middle , so that the back rows could move off to the sides if more frontage was needed . Equipment . Each phalangite carried as his primary weapon a sarissa , a double - pointed pike over 6 m ( 18 ft ) in length . Before a battle the sarissa were carried in two pieces and then slid together when they were being used . At close range such large weapons were of little use , but an intact phalanx could easily keep its enemies at a distance ; the weapons of the first five rows of men all projected beyond the front of the formation , so that there were more spearpoints than available targets at any given time . The secondary weapon was a shortsword called a kopis , which had a heavy curved section at the end . Formation . Neither Philip nor Alexander actually used the phalanx as their arm of choice , but instead used it to hold the enemy in place while their heavy cavalry broke through their ranks . The Macedonian cavalry fought in wedge formation and was stationed on the far right ; after these broke through the enemy lines they were followed by the hypaspist s , elite infantrymen who served as the king ' s bodyguard , and then the phalanx proper . The left flank was generally covered by allied cavalry supplied by the Thessalians , which fought in rhomboid formation and served mainly in a defensive role . Other forces — skirmisher s , range troops , reserves of allied hoplite s , archers , and artillery — were also employed . The phalanx carried with it a fairly minimal baggage train , with only one servant for every few men . This gave it a marching speed that contemporary armies could not hope to match — on occasion forces surrendered to Alexander simply because they were not expecting him to show up for several more days . Phalangites were drilled to perform short forced marches if required . Drawbacks . The armies of the early Hellenistic period were equipped and fought mainly in the same style as Alexander ' s . Towards the end , however , there was a general slide away from the combined arms approach back to using the phalanx itself as the arm of decision , having it charge into the enemy lines much like earlier hoplites had . This left the formation fairly vulnerable — though near invincible to frontal assault , phalanxes were susceptible to flanking , and tended to break formation when advancing quickly over rough ground . So long as everyone was using the same tactics these weaknesses were not immediately apparent , but with the advent of the Roman legion they proved fatal in every major engagement , the most famous being the Battle of Pydna , as the Romans were able to advance through gaps in the line and easily defeat the phalangites in close quarters . Advantage . The Macedonian phalanx was not very different from the Hoplite phalanx of other Greeks states , it was better trained , armed with the sarissa enabling it to outreach its competitors and stave off enemy cavalry , and wore far lighter armor enabling longer endurance and long fast forced marches , including the ability to sprint to close and overwhelm opposing positions and archers . In essence , the range of their counter - weighted sarissa , allowed them superior mobility as well as superior defense and attack abilities despite the encumbrance disadvantages of the longer weapon once trained up to handling it in formation . Centuries later , the organized militia of Swiss pikemen enjoyed similar advantages over less well trained contemporary militaries which were identically equipped , which emphasizes the importance of training and unit cohesion in the scheme . In Phillip ' s and Alexander ' s time , the Macedonian phalanx had clear technical superiority . Attempts for revival in the Roman period . Some Roman emperors were great admirers of Alexander of Macedon and attempted to imitate the Macedonian Phalanx . This is attested by Cassius Dio , Herodian and the Augustan History . Emperor Caracalla ( 2nd - 3rd century AD ) had formed a Macedonian phalanx of 16 , 000 men all born in Macedonia and commanded by officers bearing the names of Alexander ' s officers . Also Severus Alexander ( 3rd century AD ) had an imitation of the Macedonian phalanx of 30 , 000 " phalangarii " and with this he won many victories in the Persian Wars .