Question: When did the great wall of china started building?

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question: When were fortifications being built in China that became part of the Great Wall?
short_answers: 771 BC
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question: When was the official order to start building the Great Wall of China?
short_answers: 221 BC

Answer: The history of the Great Wall of China began when fortifications built by various states during the Spring and Autumn ,771 BC through 476 BC, and Warring States periods 475–221 BC, were connected by the first emperor of China, Qin Shi Huang, to protect his newly founded Qin dynasty 221–206 BC, against incursions by nomads from Inner Asia. The walls were built of rammed earth, constructed using forced labor, and by 212 BC ran from Gansu to the coast of southern Manchuria. The official order to start building the wall was in 221 BC.