The document summarizes several important Chinese dynasties from 221 BC to 1911 AD. The Qin Dynasty first centralized the government and standardized the legal code, writing system, measurements, and currency. The Han Dynasty extended the Chinese empire under Emperor Wu and established relations with the West through the Silk Road. Subsequent dynasties like the Sui reunified China, the Tang and Han were most prosperous periods, the Song experienced economic growth in Kaifeng, the Yuan was the first to rule all of China under Kublai Khan in Beijing, the Ming conquered Vietnam and expanded the Grand Canal, and the Qing created the most complete dictionary to maintain Manchu cultural identity within China.