Qin Shi Huang

Ying Zheng became king of the state of Qin as a boy and, after defeating the other warring states, declared himself Qin Shi Huang, first emperor, in 221 BCE. He unified the writing system, currency, and weights and measures, built roads and canals, and linked earlier frontier walls into an early version of the Great Wall. His rule was harsh: it relied on Legalist controls, heavy forced labour, and the suppression of dissent, and later histories accuse him of burning books and burying scholars, though the scale of that is debated. He was buried near Xi'an with the vast Terracotta Army, and his dynasty collapsed within a few years of his death.