Proto-civilisation
Proto-civilisation (French writing, British spelling) is the transitional state between a society structured as a collection of tribal chieftains, perhaps owing allegiance to a paramount chief, and the development of a full urban civilisation, in which people live in a graded hierarchy of settlement types perhaps starting with isolated peasant farms, hamlets or small villages, through market towns, to centralised capital cities or ceremonial centres. It is an important stage in the genesis of a civilisation, but historically appears to be an unstable threshold, often reverting to tribal or chieftain cultures if unable to "progress" to a full blown and semi-stable civilisation.
Examples of proto-civilisations are found preceding the development of almost all civilisations, but there are also examples of many proto-civilisations that failed to generate a separate civilisation. For example, the La Tene Celtic culture of oppida, stretching from such sites as at Hueneburg in Southern Germany, to the Belgae kingdoms of Southern Britain, show many of the characteristics of a proto-civilisation; including the settlement hierarchy already mentioned, the development of an upper "princely" class having a monopoly on institutionalised violence, the development of specialised functionaries, artisans and craftspeople. It is quite possible that this development would have led to a fully Celtic civilisation, if the areas had not been conquered by the Romans and included as the western part of the Roman Empire. The proto-civilization sites have achieved much and made a big impact on today's society. In North America, the Mississippian culture is believed to have produced proto-civilizations at such sites as Cahokia in Illinois, Moundville in Alabama, and Etowah in Georgia.