Qin Unification of China
After centuries of warfare, the state of Qin conquered all its rivals and forged China's first unified empire — then welded it together, standardizing the script, coinage, weights, and even axle-widths, and linking older walls into the first Great Wall. Its rule was brutally efficient and short-lived, collapsing within years of the first emperor's death, but the unified China it created has re-formed itself again and again for over two thousand years. Qin built not merely an empire but the very idea of China as a single state.
A durable new order — a state, an institution, a system of rule — is deliberately built and consolidated, outlasting the people who founded it.