The Qin Dynasty, founded by Qin Shi Huang, was the first to unify China in 221 BCE. While it only lasted 15 years, the Qin Dynasty had a significant lasting impact through establishing policies and practices that influenced later dynasties. Some key legacies included standardized weights and measures, a unified written language, construction of a vast road network and the Great Wall, and the terracotta army buried with Qin Shi Huang to protect him in the afterlife. The Qin also established the first centralized bureaucratic government system in China based on Legalist principles.