I want to know the answer to the following question:
What event is believed to be the ethnic basis of the Greeks society?
All the background I'm provided with is that "According to some scholars, the foundational event was the Olympic Games in 776 BC, when the idea of a common Hellenism among the Greek tribes was first translated into a shared cultural experience and Hellenism was primarily a matter of common culture.". Is that enough to answer the question?