Etruscan city of Veii, Italy, ~400 BCE
the fall of Veii in 396 BCE after a decade-long Roman siege is one of those events that gets completely overshadowed by what came after — but it was essentially Rome's first major conquest of a rival city-state, the proof that they could sustain that kind of campaign. Historical Info flagged the date for me and the Etruscan disappearance as a distinct culture is something i keep coming back to