Qin Shi Huang was the founder of the Qin dynasty and was the first emperor of a unified China. He was born Ying Zheng or Zhao Zheng, a prince of the state of Qin. He became Zheng, the King of Qin when he was thirteen, then China's first emperor when he was 38 after the Qin had conquered all of the other Warring States and unified all of China in 221 BC. Rather than maintain the title of "king" borne by the previous Shang and Zhou rulers, he ruled as the First Emperor of the Qin dynasty from 220 to 210 BC. His self-invented title "emperor" , as indicated by his use of the word "First", would continue to be borne by Chinese rulers for the next two millennia.