Thessalian cavalry

Ancient Macedonian army
Participant in Rise of Macedon, Alexander's Balkan campaign, the Wars of Alexander the Great
Hypaspist in light equipment (modern reconstruction)
Leaders	Philip II of Macedon, Alexander III of Macedon
Headquarters	Pella, Babylon
Area of operations	Greece, Balkans, Anatolia, Syria, Phoenicia, Egypt, Mesopotamia, Iran, India
Size	32,000+ - the field army for Alexander the Great's invasion of the Persian Empire - according to Diodorus Siculus. This figure fluctuated, for example at Gaugamela, Alexander commanded at least 47,000 soldiers.
Part of	Kingdom of Macedon
Became	Armies of the Diadochi - Hellenistic armies (Antigonid Macedonian army, Seleucid army, Ptolemaic army)
Allies	League of Corinth.
Opponents	Illyrians, Thracians, Phocis, Athens, Thebes, Sparta, Persian Empire, Kingdom of Porus, Scythians.
Battles and wars	Battle of Crocus Field, Battle of Chaeronea, Battle of Thebes, Battle of Granicus, Battle of Issus, Battle of Gaugamela, Battle of the Hydaspes

The army of the Kingdom of Macedonia was among the greatest military forces of the ancient world. It was created and made formidable by King Philip II of Macedon; previously the army of Macedon had been of little account in the politics of the Greek world, and Macedonia had been regarded as a second-rate power.

The latest innovations in weapons and tactics were adopted and refined by Philip II, and he created a uniquely flexible and effective army. By introducing military service as a full-time occupation, Philip was able to drill his men regularly, ensuring unity and cohesion in his ranks. In a remarkably short time, this led to the creation of one of the finest military machines of the ancient world.

Tactical improvements included the latest developments in the deployment of the traditional Greek phalanx made by men such as Epaminondas of Thebes and Iphicrates of Athens. Philip II improved on these military innovators by using both Epaminondas' deeper phalanx and Iphicrates' combination of a longer spear and smaller and lighter shield. However, the Macedonian king also innovated; he introduced the use of a much longer spear, the two-handed pike. The Macedonian pike, the sarissa, gave its wielder many advantages both offensively and defensively. For the first time in Greek warfare, cavalry became a decisive arm in battle. The Macedonian army perfected the co-ordination of different troop types, an early example of combined arms tactics — the heavy infantry phalanx, skirmish infantry, archers, light and heavy cavalry, and siege engines were all deployed in battle; each troop type being used to its own particular advantage and creating a synergy of mutual support.

The new Macedonian army was an amalgamation of different forces. Macedonians and other Greeks (especially Thessalian cavalry) and a wide range of mercenaries from across the Aegean and Balkans were employed by Phillip. By 338 BC, more than a half of the army for his planned invasion of the Achaemenid Empire of Persia came from outside the borders of Macedon — from all over the Greek world and the nearby barbarian tribes such as the Illyrians, Paeonians, and Thracians.