Answer :
The characteristics that pulled the Greek city states together where the poetry of Homer and the food growth and preparation.
The first, the poetry of Homer, is what defined the culture aspect of the Greek societies, as it was the most important poet at the time. Homer' poetry where taught in all the greek polis (the greek name for city-states) and it was the base of school at the time, for those who had the priviledge to learn how to write and read. Other people were instructed in the poetry by listen to people who had to memorizied the poem.
The second, the food growth and preparation, comes from the natural resources of Greece. The type of soil and the morphology of the territory allowed for very specific culture, that become the base of food in the country.
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The characteristics that pulled the Greek city states apart where the culture within the city-state, the loyalty to the polis and different languages. As for the first, every polis had its own culture. For example, Athens were focused on democracy and culture, while Sparta was all about war and competition. The loyalty to the polis was fundamental in the education, as it was the first and most important institution which greek people at the time should be loyal to. Besides from these facts, different languages did not help different polis come together, as the linguistic barrier could be a serious difficulty to overcome at the time as today.
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Oligarchy is a form of government in which a small group (oligo-) holds all the power(archy). Many polis were hold by an oligarchy. It was the most common form of government at the time. how the oligarchy was selcted was different from polis to polis. For example, Athens used to held election - altough those were reserved to the male, medium and high classes people.
