During the Greek Dark Ages, the Greeks lived in small tribal units; some of these small tribes were sedentary and agricultural and some were certainly nomadic. They had abandoned their cities between 1200 and 1100 BC for reasons that remain shrouded in mystery; the Greeks believed that a cataclysmic and ferocious invasion of northern Greek barbarians, the Dorians, had wiped out the Mycenean civilization. In reality, the decline and abandonment of urbanization in Greece was probably due to a combination of economic collapse and pressure from northern migrations. Greek life during the "Dark Ages" wasn't dark; it was, in fact, a culturally creative period. This period gave the Greeks the religion their religion, mythology, and foundational history in their final forms; the close of the Dark Ages would also gave the Greeks the rudiments of their greatest political achievement: the polis , or "city-state."
The tribal or clan units of the dark ages slowly grew into larger political units; beginning around 800 BC, trade began to dramatically accelerate between the peoples of Greece. Marketplaces grew up in Greek villages and communities began to gather together into defensive units, building fortifications to use in common. On this foundation, the Greek-speaking people on the Greek peninsula, the mainland, and the coast of Asia Minor, developed political units that were centrally based on a single city. These city states were independent states that controlled a limited amount of territory surrounding the state. The largest of these city-states, for instance, was Sparta, which controlled more than 3000 square miles of surrounding territory.
The period in which the city-states evolved is called the Archaic Period; while the separate states had close interaction with one another during this time and certainly learned political organization from one another, in many ways, however, each city-state developed fairly unique and independent cultures and political organizations (notice that the word "political" is derived from the word polis ).
Politically, all the Greek city-states began as monarchies. In their earliest stages, they were ruled by a basileus , or hereditary king. The Greeks living in those city-states, however, soon tired of the kings, many of which were overthrown in the eighth century BC. A variety of political alternatives were put in place of the basileus : the most common was an oligarchy, or "rule by a few." The oligarchs were almost always drawn from the wealthiest citizens of the state ("rule by the wealthy" is called a timocracy), but a variety of oligarchic forms were invented in the eighth century. The oligarchs most often ruled absolutely; they had many of the powers granted to a king. Even though these powers were diffused among a group (which could be surprisingly large), the power of the oligarchy could be remarkably totalitarian. Most of the early oligarchic governments and a few of the kings were overthrown by "tyrants" (in Greek, tyrranos); while Greek history is generally unkind to the tyrants, we can through the haze of later Greek propaganda come to some dispassionate conclusions about the nature of the tyrranies. The Greeks believed that the tyrants were illegitimate usurpers of political power; they seem, however, to have had in many cases popular support. The Greek tyrants were often swept into power by dissatisfaction or crisis; they were more often then not extremely popular leaders when they assumed the tyrrany. Once in power, they ruled as a king would rule, and many attempted to make (and some succeeded) the tyrrany hereditary—in essence, a form of monarchy. Many of them seem to have directed their attentions to the crisis that swept them into office, but most of them set about shoring up their shaky hold on power. For the tyrants ruled only by a thread; they maintained power only by their hold on military force and often fear. The tyrranies were by nature highly unstable, and they fell apart rapidly. Even so, tyrrany was a widespread political institution throughout the Greek-speaking world: tyrranies were experimented with not only in Greece, but Asia Minor and even as far away as the Greek cities in Sicily.
By the sixth century, the experiments began to settle around two alternatives. The tyrranies never died out, but oligarchy became the settled norm of the Greek city-states. Several of these oligarchies, however, were replaced by a second alternative that originates sometime in the sixth century: democracy. The word means, "rule by the demos (people)," but the Greek democracies looked nothing like modern democracies. First, they really mean rule by the people; the Greek democracies were not representative governments, they were governments run by the free, male citizens of the city-state. Second, all the people were not involved in the government: slaves, foreigners, and women were all disbarred from the democracy. So, in reality, the democratic city-states more closely resembled oligarchies for a minority—a very large minority, to be sure— ruled the state.
This was a period of frenetic colonization. The Greeks, pressured by growing populations around the city-states, actively went looking for unpopulated or thinly populated areas to colonize in Greece, the Aegean Sea, and elsewhere. The Greek city-state began to appear on the Italian and Sicilian shores, and set up trading posts in the Middle East and Egypt. Greek culture was spreading across the Mediterranean, and Greek commerce was rapidly making the city-states wealthy and powerful. There was no military, political, or cultural center of the Greek world in the Archaic period. Different city-states developed separate cultures; these developments, however, spread across the Greek world. The city-state culture, then, was in many ways a national culture because of the dynamic interactions between the city states. The greatest flowering of culture occurred on the city-states of Asia Minor, and especially Miletus. Greek philosophy begins in these city-states and soon spreads around the Greek world. Corinth and later Argos became great centers of literature. But perhaps the greatest of the city-states were Athens and Sparta. Sparta in particular dominated the political scene all during the seventh century BC, and would remain a powerful force all throughout its history until the Macdonians conquer Greece in the fourth century BC.