Traditional explanations turn to idea of rise of the "gens," something which @rometostandrews has convincingly debunked, infra alia (a) because the ancient Roman gens was not a stable concept and (b) this phenomenon goes far beyond Rome's orbit
-Why trend across all Italy at this particular time? Seemingly everywhere we see radical spatial transformation as enormously wealthy elites consolidate and propagate political power
Climate change and production? Metallurgy + early iron weaponry? Greek colonial presence in Bay of Naples? Lots to think about. There's prob some lesson too about historical inequality, but I'm tired and so will stop.