The Greek civilization was basically maritime, commercial and expansive. A historical reality in which the geographic component played a crucial role to the extent that the physical characteristics of the southern Balkan peninsula made it difficult for agricultural activity and internal communications, while its long coastal length favored its expansion towards overseas .
A phenomenon that would also have a substantial impact on the demographic pressure caused by the successive waves of peoples (among them the Achaeans, the Ionians and the Dorians) who invaded and occupied the Hellas throughout the III and II millennium BC.
The first Greeks were organized into family clans. Over time, the clans allied and formed communities, although they were separated from each other due to the mountainous relief of the region. This favored their becoming independent territories with their own government and army. In ancient Greek those populations were called polis. Despite sharing essentially the same geographical space, language and culture, the political organization of the polis was very diverse, including a wide range of systems of government, ranging from tyranny to democracy. The polis were the true political unit, with its institutions, customs and laws.
It seems that at first many Greek city-states were minor kingdoms; many times there was a municipal official who performed the king's duties. Later, most of these city-states had already become aristocratic oligarchies. It is not known how this change happened.
Athens fell under a tyranny in the second half of the sixth century BC. When this tyranny ended, the Athenians founded the first democracy in the world. An assembly of citizens for the discussion of municipal policy and all citizens were allowed to attend. By establishing democracy, the assembly became the mechanism of government; all citizens then had equal rights in the assembly.
