Ancient Greek warfare of the phalanx to its logical completion, arming his 'phalangites' (for they were assuredly not hoplites) with a fearsome pike, the 'sarissa'. Much more lightly armored, the Macedonian phalanx was not so much a shield-wall as a spear-wall. The Macedonian phalanx was a supreme defensive formation, but was not intended to be decisive offensively; instead, it was used to pin down the enemy infantry, whilst more mobile forces (such as cavalry) outflanked them. This 'combined arms' approach was furthered by the extensive use of skirmishers, such as peltasts. Tactically, Phillip absorbed the lessons of centuries of warfare in Greece. He
Thracian warfare tribal wars also kept Thrace from becoming a major regional power due to the lack of a central government. At the onset of the Peloponnesian War, the Thracian tribes were united under the rule of Sitalces, king of the Odrysae. It was allied with Athens during the conflict. However, the kingdom was again split into different parts after the death of king Seuthes. It was during this time when Philip of Macedon conquered a large swath of Thrace, absorbing the territory and its tribes into Macedon. The "Odrysian kingdom" (Ancient Greek, "Βασιλεία Όδρυσων") was a union of Thracian tribes that