The Warring States period marked a time in China when several states battled each other for power. Through this time, various philosophers developed different schools of thought on how to restore order to society.
One state, the Qin, built a strong army that defeated the armies of the rivaling states. Eventually, the Qin dynasty united the country under one (1) government.
The Qin king, Ying Zheng, successfully unified China. He gave himself the title of Shi Huangdi and followed Legalist political beliefs while he ruled. He created a strong central government with strict laws and harsh punishments.
Qin Shi Huangdi altered China's political system, claiming all the power for himself and sharing none of it with the lords. He also took land from the nobles and forced them to move to the capital of his empire so that he could keep an eye on them.
He forced thousands of commoners to work on government building projects, facing years of hardship, danger, and even death.
To control China, Shi Huangdi divided the country into districts, each with its own governor. Districts were further divided into counties governed by appointed officials. (This system is similar to the United States: a country divided into states, and each state divided into counties...) This organization helped the emperor impose his tax system and reinforced a strict chain of command.
You are a scholar living in China in 210 B.C.E. You have a large library of Chinese literature, poetry, and philosophy. The new emperor is a harsh ruler with no love for learning. He says you must burn all the books that disagree with his ideas. This declaration horrifies you, but if you do not obey, the punishment may be severe.
The cruelties endured by the Qin were later used by historians as "evidence" that the Qin had ruled poorly, thus losing the "Mandate of Heaven" and allowing for the Han dynasty to take over and control China.
It winds its way through the countryside of China. As it turns out, the wall's history is almost as long and serpentine as its structure.