In order to protect the various dynasties from raids by Mongol, Turkic, and other nomadic tribes coming from areas in modern-day Mongolia and Manchuria. Because to prevent the Mongols from entering and invading China.
Although a useful deterrent against raids, at several points throughout its history the Great Wall failed to stop enemies, including in 1644 when the Manchu Qing marched through the gates of Shanhai Pass and replaced the most ardent of the wall-building dynasties, the Ming, as rulers of China.  Several walls were being built as early as the 7th century BCE; these, later joined together and made bigger and stronger, are now collectively referred to as the Great Wall. Especially famous is the wall built 220–206 BCE by Qin Shi Huang, the first Emperor of China. Before the use of bricks, the Great Wall was mainly built from rammed earth, stones, and wood. During the Ming, however, bricks were heavily used in many areas of the wall, as were materials such as tiles, lime, and stone. It's well known that Emperor Qin built the Great Wall. But the history of the Great Wall is not that simple. Emperor Qin was not the first to build the Great Wall... or the last. There are many sections in different places, built with different materials, and built in different dynasties. The emperors of the Qing Dynasty (1644–1911) didn't build the Great Wall and even forbade it: they were Manchurians, who the Great Wall was built to keep out. The Xiongnu tribe was China's main enemy at that time. The Chinese built the Great Wall to prevent them from entering and conquering China. Originally made up of shorter walls between factions, the wall was fortified and lengthened under the emperor Qin Shi Huang beginning in 221 BC. The Great Wall of China was built from the 3rd century B.C.E to the 17th century AD, in order to prevent the Mongols from entering and invading China. *Please see the relate … d questions and link below for more information. The Great Wall stretches from Dandong in the east, to Lop Lake in the west, along an arc that roughly delineates the southern edge of Inner Mongolia. A comprehensive archaeological survey, using advanced technologies, has concluded that the Ming walls measure 8,850 km (5,500 mi). Before the use of bricks, the Great Wall was mainly built from rammed earth, stones, and wood. During the Ming, however, bricks were heavily used in many areas of the wall, as were materials such as tiles, lime, and stone. Great Wall was constructed with the view that it will keep out Mongol invaders who frequently attacked from Northern side. The Great Wall is not a single structure. Different sections were constructed under different emperors and dynasties. The first section was constructed under Qin Dynasty. Today, many famous Great Wall sections and ruins that belong to different dynasties are still remained in Xinjiang, Gansu, Ningxia, Shaanxi, Inner Mongolia, Shanxi, Hebei, Beijing, Tianjin, Liaoning, Jilin, Heilongjiang, Henan, Shandong, Hubei, and Hunan etc. The great wall consists of different sections and has an amazing length, but why was it built, what was the purpose of the great wall. Related article: the construction of the Great wall of China. Because the walls were built of mud, gravel, and wood, repairs were often necessary. The wall that is seen today was mainly built by the Ming Dynasty in the 1400's B.C. Most of the artisans from this later time used stronger elements in the construction such as bricks and stone. The Great Wall of China is a Chinese fortification built from 3rd century BC until the beginning of the 17th century, in order to protect the various dynasties from raids by Mongol, Turkic, and other nomadic tribes coming from areas in modern-day Mongolia and Manchuria. The Great Wall of China was built from the 3rd century B.C.E to the 17th century AD, in order to prevent the Mongols from entering and invading China. *Please see the relate … d questions and link below for more information. He destroyed walls between states and ordered the main wall along the northern border of the territory to be extended. Later dynasties repaired and rebuilt the Great Wall of China along the northern border to continue to deter those northern tribes from raiding. Because the walls were built of mud, gravel, and wood, repairs were often necessary. The wall that is seen today was mainly built by the Ming Dynasty in the 1400's B.C. Most of the artisans from this later time used stronger elements in the construction such as bricks and stone. Better materials made for a much more permanent structure
https://en.wikipedia.org/wiki/History_of_the_Great_Wall_of_China https://en.wikipedia.org/wiki/Great_Wall_of_China http://www.chinahighlights.com/greatwall/fact/who-built.htm http://www.answers.com/Q/Why_was_the_Great_Wall_of_China_built https://en.wikipedia.org/wiki/Great_Wall_of_China https://answers.yahoo.com/question/index?qid=20090608111152AAoh7H3 http://www.great-wallofchina.com/why-was-the-great-wall-of-china-built.html http://www.answers.com/Q/Why_was_the_Great_Wall_of_China_built http://www.great-wallofchina.com/why-was-the-great-wall-of-china-built.html
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