Why did they build the great wall of china?
Great wall was first built in 656BC- maybe eariler in the state of Chu. Seperate states tore apart the nation at the time as they fought wars with each other. The wall of the state of Chu built for military defense and proved to be effective. Then other states followed suits. The lenght of wall of each state vary from a few hundred kms to one or two thousand. ALL these walls failed to block the advanced of armies of the Qin state. In the year 221BC, Emperor Shihuang unified the country and established the Qin,China’s first feudal dynasty. For a time, those walls seems no longer necessary. However, the nomadic Xiongnu ethnic group in the north often made incursions into the Qin territory. To defend the empire’s northern borders, emperor shihuang ordered a project to have the walls linked up and extended. That’s how the Great wall came into being, extending east to west for well over 5000kms.