Such new weaponry , used by a proto-hoplite model of infantry able to withstand attacks of massed chariotry , would destabilize states that were based upon the use of chariots by the ruling class . This precipitated an abrupt social collapse as raiders and\/or infantry mercenaries began to conquer , loot , and burn the cities . Such new weaponry , furnished to a proto-hoplite model of infantry which was able to withstand attacks of massed chariotry , would destabilize states that were based upon the use of chariots by the ruling class and precipitate an abrupt social collapse as raiders and\/or infantry mercenaries began to conquer , loot , and burn the cities .