Answer:
Mostly because of the geographical features
Step-by-step explanation:
Primarily, the Greek communes were divided, distant and isolated due to geographical areas, islands, inaccessible landscapes and most of all because of the mountains that made it difficult to come from place to place.
Also in the ancient Greek people within the country itself did not always agree with each other, as we have a great example of Athens and Sparta.
Later, however, in spite of the inaccessible landscapes and distances, the people merged first into the Polis ( city ) and later on into the city-states.