For most of history Greece was an amalgam of independent and sovereign city states that often warred amongst each other. They were united by language and similar culture although customs differed amongst different states. For instance the Athenians for a while practiced a form of democracy and promoted the arts, while the Spartans where a highly militaristic oligarchy focused on warfare. The city states occasionally banded together politically when faced with a foreign threat, like in the case of the Greco-Persian wars. Eventually the ancient Greece was united politically, first under the Athenian and later Spartan hegemony. Eventually the Macedonian empire (itself of a Greek based culture) came to dominate all of ancient Greece.