Question: when did the construction of the great wall of china start

title: History of the Great Wall of China
text: One of the first mentions of a wall built against northern invaders is found in a poem , dated from the seventh century BC , recorded in the Classic of Poetry . The poem tells of a king , now identified as King Xuan ( r . 827 -- 782 BC ) of the Western Zhou dynasty ( 1046 -- 771 BC ) , who commanded General Nan Zhong ( 南仲 ) to build a wall in the northern regions to fend off the Xianyun . The Xianyun , whose base of power was in the Ordos region , were regarded as part of the charioteering Rong tribes , and their attacks aimed at the early Zhou capital region of Haojing were probably the reason for King Xuan 's response . Nan Zhong 's campaign was recorded as a great victory . However , only a few years later in 771 BC another branch of the Rong people , the Quanrong , responded to a summons by the renegade Marquess of Shen by over-running the Zhou defences and laying waste to the capital . The cataclysmic event killed King Xuan 's successor King You ( 795 -- 771 BC ) , forced the court to move the capital east to Chengzhou ( 成 周 , later known as Luoyang ) a year later , and thus ushered in the Eastern Zhou dynasty ( 770 -- 256 BC ) . Most importantly , the fall of Western Zhou redistributed power to the states that had acknowledged Zhou 's nominal rulership . The rule of the Eastern Zhou dynasty was marked by bloody interstate anarchy . With smaller states being annexed and larger states waging constant war upon one another , many rulers came to feel the need to erect walls to protect their borders . Of the earliest textual reference to such a wall was the State of Chu 's wall of 656 BC , 1,400 metres ( 4,600 feet ) of which were excavated in southern Henan province in the modern era . The State of Qi also had fortified borders up by the 7th century BC , and the extant portions in Shandong province had been christened the Great Wall of Qi . The State of Wei built two walls , the western one completed in 361 BC and the eastern in 356 BC , with the extant western wall found in Hancheng , Shaanxi . Even non-Chinese peoples built walls , such as the Di state of Zhongshan and the Yiqu Rong ( 義 渠 ) , whose walls were intended to defend against the State of Qin . 

Answer: answer: One of the first mentions of a wall built against northern invaders is found in a poem, dated from the seventh century BC. However,  the State of Wei built two walls, the western one completed in 361 BC and the eastern in 356 BC.
answer: With smaller states being annexed and larger states waging constant war upon one another , many rulers came to feel the need to erect walls to protect their borders. Of the earliest textual reference to such a wall was the State of Chu 's wall of 656 BC. The State of Qi also had fortified borders up by the 7th century BC , and the extant portions in Shandong province had been christened the Great Wall of Qi .