:matrix: Civilization is an outcome of strong culture and religion of the society!!! Strong cultural and religious growth play important role for a strong society, gives strong identity to one society which initiates other small societies to join or bigger population of same society who follow their ideology. Thus a large and strong and large society is established. So Cultural and religious growth of the society in one era is civilization.

Society’s identity is its culture and religion. Each society has its own identity but when it weakens against the strong due to deficiency, people divert or merge with strong one. And society extends to other parts to become stronger and stronger. Thus that society becomes the strongest society of the era with most population accepting its ideology.
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Measurement of the strength of the civilization is based on quality of life: behavior, art, ritual practices, faith, language, food habits, intelligence and economy etc; each strong society has its strong identity that popularizes.

From an historian's perspective civilization is living in cities. When man began to live in cities it necessitated some form of governmental heirarchy, one of the prime indicators of civilization.

Would that not have begun in tribal leaders,before cities came along.