The polis is the city-state of ancient Greece where Greek politics, commerce and creative culture was centered. It developed from the Archaic period and is considered the ancestor of the terms city, state and citizenship. It was the central urban area that may have some degree of rule over the surrounding countryside. Among the Greek polis were Athens, Thebes and Sparta which were considered independent with each other. The polis is typically bounded around a citadel or an acropolis and would essentially have a market called the agora and would usually have one or more places of worship and a gymnasium.
The Greeks considered the polis or city-states as a unique institution because in ancient times, it was the first gathering of people wherein the rulers or officials were elected by the people and laws were passed. Although the polis was composed of several tribes or demes, it was ruled not by a particular king or oligarchy but rather considered as a political entity ruled by the inhabitants or citizens themselves. To some extent, there is a high degree of citizen involvement and participation in the management of the public organization in a polis. The polis was considered as the most significant contribution in politics of the Greek people.
The fundamental difference between the ancient Greek polis and a modern day country city like that of Western Europe or America is that the Greeks did not consider the polis as under any sovereignty while a modern age city is necessarily under a sovereign country or state. In other words, the polis is an autonomous entity while a modern city is positively positioned in a sovereign state. The polis is not identified by territory but rather by the citizenship of its people whereas a modern city is generally set apart by land area and population. Their similarities lie greatly in them being both centers of commerce, artistry, politics and the melting pot of state development.
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[Electronic Version]. Retrieved April 28, 2008 from http://wps.prenhall.com/hss_king_westernciv_2/3/809/207260.cw/index.html.