The first evidence of horses in warfare dates from Eurasia between 4000 and 3000 BC. A Sumerian illustration of warfare from 2500 BC depicts some type of equine pulling wagons. By 1600 BC, improved harness and chariot designs made chariot warfare common throughout the Ancient Near East, and the earliest written training manual for war horses was a guide for training chariot horses written about 1350 BC. As formal cavalry tactics replaced the chariot, so did new training methods, and by 360 BC, the Greek cavalry officer Xenophon had written an extensive treatise on horsemanship. The effectiveness of horses in battle was also revolutionized by improvements in technology, such as the invention of the saddle, the stirrup, and the horse collar.

Heavy cavalry was a class of cavalry intended to deliver a battlefield charge and also to act as a tactical reserve; they are also often termed shock cavalry. Although their equipment differed greatly depending on the region and historical period, heavy cavalry were generally mounted on large powerful warhorses, wore body armor, and armed with either lances, swords, maces, flails (disputed), battle axes, or war hammers; their mounts may also have been protected by barding. They were distinct from light cavalry, who were intended for raiding, reconnaissance, screening, skirmishing, patrolling, and tactical communications.