Zhu Yuanzhang used to be a peasant, a buddhist monk and a soldier. He had got lots of experience during his poor life. After seventeen years' army life, he became a emperor. As a emperor, he was still very frugal and fond of learning, he was concerned about the common people, and began to reform after the war ended. Actually, he was considered as one of the greatest emperors.

There were several emperor who used to be a common people. For example:
Emperor GaoZu of Han Dynasty Liu Bang,
Emperor TaiZu of Ming Dynasty Zhu Yuanzhang