Heavy cavalry

Heavy cavalry is a class of cavalry whose primary role was to engage in direct combat with enemy forces. Although their equipment differed greatly depending on the region and historical period, they were generally mounted on large powerful horses, and were often equipped with some form of scale, plated, chainmail or lamellar armour as well as either swords, maces, lances, or battle axes.

Although some form of cavalry had been in use in Mesopotamia since 3000 BC, the chariot was the predominant mobile striking force of most armies in the region. By 600 BC armoured cavalry began seeing use, though it was not until the later ancient Greek era that true heavy cavalry emerged. Assyrian cavalry during the reign of Ashurbanipal was known to have used metal helmet and breastplate, fought with thrusting spears in conjunction with bows and arrows, and rode on horses covered with textille barding, however it's unclear how this early heavy cavalry operated and performed.

Iranian tribes such as the Massagetae were believed to be the originator of the class of heavy cavalry known as cataphract. During the time of Achaemenid Persia cavalry was the elite arm of service (as was the case in most civilizations), and many Persian horsemen such as the bodyguard unit of Cyrus the Younger were rather heavily armoured by the standards of the era. By the time of Alexander's invasion cataphract units with both men and beasts being fully encased in armour were already in use by the Persians.

The Parthian Empire of Ancient Iran marks an early recorded utilization of armoured cavalry in warfare, and are specifically believed to have given rise to the tradition of very heavily armoured cataphract lancers. These had a distinct role from ordinary heavy cavalry and were primarily used as an elite assault force, to pummel infantry formations into submission, or even acted in a dual-purpose role as horse archers and cataphracts.

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