Birth of Cavalry
The large scope of military action forced the Assyrians to fight in all types of terrain, a condition to which the heavy chariot was ill-suited. A major Assyrian revolution in battlefield capability was the invention of cavalry. Assyrian cavalrymen used the saddle girth, crupper, and breast strap to stabilize the rider, and the horse was controlled by the leg and heel pressure of the boot. (The spur and the stirrup had not yet been invented.) These innovations made possible the first use of mounted archers, the famed ‘hurricanes on horseback’ mentioned in the Old Testament. In set-piece battle the cavalry was used to pin the enemy flanks and to take up blocking positions to prevent a retreat. Once in position behind the enemy, the cavalry acted as an anvil against which the chariot and infantry units could drive the enemy. The ability of the horse to traverse uneven terrain made the cavalry especially lethal in the pursuit. This same ability made cavalry forces highly flexible and valuable for reconnaissance in force and for providing flank security for the army on the march, two new tactical capabilities.
The Persians expanded the role of the cavalry in their fighting formations. By the time of Cyrus, the Persian army’s ratio of cavalry to infantry was 20 percent cavalry to 80 percent infantry. It was the largest cavalry force in the world. Although an elite force, Persian cavalry was used primarily to draw the enemy into infantry battle….
— From Sumer To Rome, p. 32