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Quite simply when people think of Etrusca replacing Rome they think of an Etruscan Empire, which frankly was impossible.

With that said, what if Etrusca simply won the Roman-Etruscan Wars putting Rome and her city states under Etrusca. Effectively except for a few Greek city states, who would likely later join the League, making Etrusca the rulers of the Italian Peninsula.

What happens now? Will the Etruscan League become more unified? Will Etrusca have a war with Carthage like Rome did or will the two tolerate each other because Etrusca had little to no interest in Sicily? Will Greeks be a more wide spread ethnic group? Could Etrusca even survive if so, for how long?

Anything else besides just the obvious European, North African and Middle Eastern cultures will be very different from what we know it without a Roman Empire.
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