AFAIK germanic and celtic people saw themselves as memberes of their respective tribes, beginning at the family level and united in greater (and sometimes changing) alliances led by a king in times of war. They did not think of themselves as nations or as an entity of germans or celts. Surely they recognized that they spoke the same or at least a closely related language and had some customs and most of their gods in common, but that is not necessary a reason to view themselves as one people (as can be seen in modern times in various instances, for example ex-yugoslavia and in a certain way germany till the beginning of the 19th century).
The greeks identified themselves primarily with their hometown, but I think there was at least a certain community, exemplified by pan-hellenic games (like olympia) or a feeling of community in times of external dangers (like the persian imnvasion).![]()
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