Today, knowledge of greek culture from 1150–750 bce primarily is derived from

Oral histories that later were written down.

Explanation:

The Dorians were the new group of Greeks that destroyed the Minoan and Mycenaean civilizations. Since the Dorians were a less advanced civilization, throughout their rule, the tradition of writing was left aside.  400 years went by without any written accounts. However, history was transferred over the generations by oral tradition. This is why this period was deemed the dark age of Greece.

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