City-States of the "Classical" Greek Era
Mykeneaen culture was dominated by strong single-family dynasties and their picked household troops, who defended themselves against invaders and collected taxes from surrounding settlements to support their high-tech military technology of gold- and silver-decorated bronze weapons. After the fall of the Mykenean "megaron" or great-hall cultures, to natural disasters or to internal warfare or to the unknown invaders, which destroyed them within about a century after 1100 BCE, few historical records survive. Gradually, beginning with the settlements around the ruins of the major fortresses Athens, Thebes, and Pylos, there arose complex, multi-clan societies which developed a variety of consensus-building customs related to public debate among a much wider command structure composed of citizens or members of the demos, the inhabitants of the polis or city-state.
City-states remained common from this period until the beginning of the modern era (C15-17 CE). The city-state proved to be a durable social unit because the multiplicity of families guaranteed many sources of political power rather than a single vulnerable biological line, and their united force could develop agriculture, trade, and military defense systems that were far more robust than the concentrated individualistic power-centers of the megaron households. See the horrible danger Aeschylus exposes in the Oresteia when a palace coup enables Clytemnestra and her husband's nephew to seize control, exiling the rightful heir and virtually enslaving the rest of the bloodline. In effect, that trilogy's development of the rule of Athenian law courts rejects the megaron's vengeance-based definition of justice as exercise of the nobility's "rights" (the older sense of dikê) in favor of a shared satisfaction of communal laws that could adapt to changing circumstances (the newer definition of dikê).
Like their predecessors, the city-states required walled fortifications to protect them from invading armies of other city states, with which they went to war quite often. The akropolis or "high-city" on the highlands above each city-state became a citadel into which the demos could retreat if their armies met utter defeat. The major change in the battle tactics from the older Bronze-age warfare was the shift from one-on-one combat in a melee of chariots and armed men, to a disciplined clash of tightly-grouped men who had linked together their shields in a phalanx or "shield-wall." This presented to the opposing army a nearly impenetrable armor against projectiles, and from between each pair of shields protruded a long spear, the phalanx's offensive weapon. Charging the enemy's shield wall while maintaining the shield-wall's integrity required superior athletic training and mental discipline. The failure of even one warrior to hold his place in line could result in the collapse of the entire defensive structure.
When two phalanxes met, the shock of the impact tested the strength and will of both armies, and one usually broke ranks and ran. This turning away from battle, or "trope," was marked on the battlefield by the weapons discarded by the losing soldiers to give them speed to evade pursuers. At this place on the battlefield, the victorious army would erect a pile of the captured weapons, a "trophe" or monument to the victory. These "trophies" recur in celebrations of military victory from the sixth century BCE to the Renaissance, and in battlefield memorials from the various wars of Europe in the nineteenth and twentieth centuries. The trophy celebrated the city's victory through the coordinated force of its citizens, rather than any single man's triumph. That state of mind says a lot about the mentality of the demos of the Greek city-state.