This period is often called the age of the chariot. It is a very wide expanse of time and cultures from ancient Sumer to the fall of Assyria and the rise of the Medes, Persians and Greeks, and the Classical Age.
In this age the first great states with organized armies appear. Bronze is introduced to warfare as is the wheel, the phalanx, and archery. This is the period when the foundations upon which the armies of the Classical Period were laid.