Armies and Guards from the Pharaohs to the Mongols

The Egyptian army grew from regional militia forces in the Old Kingdom into a professional standing army by the New Kingdom, roughly 1550 to 1070 BC. Infantry with spears, axes and composite bows were joined by two-man chariots after contact with the Hyksos, and inscriptions describing the Battle of Kadesh around 1274 BC against the Hittites record its divisions, each tied to a god such as Amun, Ra, Ptah or Set.

The Neo-Assyrian army, roughly 911 to 609 BC, is widely seen as the first genuinely professional standing force of the ancient world. It combined infantry, cavalry, chariots and siege engineers, used iron weapons, and relied on battering rams, siege towers and tunneling. The atlas records large-scale cavalry use and new siege techniques as its signal military innovations.

The Immortals were the elite infantry corps of the Achaemenid Persian Empire. Greek writers gave them the name because any loss was replaced at once, holding the corps at 10,000 men. Recruited from Persians, Medes and Elamites, they served as royal guard and strike force under Cyrus the Great, Darius I and Xerxes I, including the invasion of Greece described by Herodotus.

Sparta built its army on citizen hoplites called Spartiates, trained from childhood in the agoge and freed for full-time soldiering by helot labor. The stand of the 300 at Thermopylae in 480 BC became its emblem, and its hoplites were decisive at Plataea in 479 BC. The defeat at Leuctra in 371 BC showed that a narrow citizen body could not sustain that dominance.

The Sacred Band was a Theban unit of 300 hoplites organized as 150 pairs of male lovers, on the theory that men fight hardest beside a partner. Raised around 378 BC, it spearheaded the Theban victories at Leuctra in 371 BC and Mantinea in 362 BC that broke Spartan dominance. It was wiped out at Chaeronea in 338 BC by Philip II and Alexander.

Philip II turned Macedonian soldiering into a full-time profession from 359 BC. He armed the infantry with the long sarissa pike in a deep phalanx and made the Companion cavalry a decisive shock arm. Alexander inherited this army and used its combined-arms flexibility to conquer the Achaemenid Persian Empire.

The Companions were the Macedonian elite heavy cavalry, drawn from the nobility and riding without stirrups with the long xyston lance. Led by Alexander at the head of the royal squadron, they delivered the decisive wedge charge at the Granicus, Issus and Gaugamela. The name comes from the king's aristocratic Companions, who supplied their own horses.

The army Hannibal led in the Second Punic War was not a citizen levy. It bound Iberian, Gallic, Numidian, Libyan and Greek troops through mercenary and allied contracts, with African and Libyan heavy infantry as a veteran core and North African war elephants as a shock weapon. Numidian light cavalry became a decisive arm at Cannae.

Numidian horsemen were light, unarmored javelin throwers prized for speed rather than shock combat. Hannibal used them on his flanks, as when luring the Romans into a trap at the Trebia. At Zama the king Masinissa had changed sides, and his horsemen fighting for Scipio helped break the Carthaginian cavalry.

The Parthian army, 247 BC to 224 AD, centered on armored cataphract lancers and horse archers who fired backward while retreating at a gallop. Noble families supplied and commanded their own contingents rather than the state fielding one standing army. The result was great mobility, shown when it destroyed a Roman army under Crassus at Carrhae in 53 BC.

Augustus formed the Praetorian Guard around 27 BC as the emperor's personal bodyguard, based at the Castra Praetoria in Rome. Its closeness to the throne made it a political force that repeatedly made and unmade emperors, most infamously by auctioning the throne to Didius Julianus in 193 CE. Constantine I disbanded it in 312 CE after it backed Maxentius at the Milvian Bridge.

The Byzantine army continued the Eastern Roman system for over a thousand years and, from about the seventh century, was organized around the theme system of provinces supporting local soldier-farmers. Manuals such as the Strategikon and the Taktika of Leo VI stressed discipline, intelligence and avoiding needless battle. Manzikert in 1071 against the Seljuks was a turning point from which its strength never fully recovered.

The Varangian Guard was formed in 988 when Basil II received 6,000 Rus warriors from Vladimir I of Kiev in exchange for a dynastic marriage. Outsiders with no stake in court politics, these axe-wielding guards served as the emperor's last line of defense, and later recruits included Harald Hardrada and Anglo-Saxon exiles after 1066. Compare this solution with the Praetorians, who were native to the capital they threatened.

At the 1206 kurultai Genghis Khan reorganized the Mongols into a decimal structure. Every man from fifteen to seventy was conscripted into a minqan of a thousand, divided into hundreds and tens, and tribes were deliberately mixed to replace clan loyalty with loyalty to the new state. It is the last and most thoroughly mounted army on this path.