 <translate> The history of the Great Wall of China began when fortifications built by various states during the Spring and Autumn (771 -- 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 labour, and by 212 BC ran from Gansu to the coast of southern Manchuria.

Answer this question based on the passage: when was the great wall of china first built? OK. Let's think. My stream of consciousness: <yor> Ìtàn Òdì-òdì Ńlá ti Ṣáínà bẹ̀rẹ̀ nígbà tí àwọn odi tí àwọn orílẹ̀-èdè ọ̀tọ̀ọ̀tọ̀ kọ́ ní àsìkò Ìrúwé àti Òṣùpá (771 - 476 Ṣ.K.) àti àsìkò Àwọn Orílẹ̀-èdè tó ń jagun (475 - 221 Ṣ.K.) ni olú ọba Ṣáínà àkọ́kọ́, Qin Shi Huang, so pọ̀ láti dáàbò bo ìdílé Qin tí ó ṣẹ̀ṣẹ̀ dá sílẹ̀ (221 - 206 Ṣ.K.) kúrò lọ́wọ́ àwọn àjèjì tí wọ́n ń wá láti Àárín Ásíà. Àwọn ògiri náà ni wọ́n fi ilẹ̀ tí wọ́n fi ọ̀pá gbá kọ́, tí wọ́n fi ipá kọ́ ọ, nígbà tó sì fi máa di ọdún 212 ṣáájú Sànmánì Kristẹni, ó ti bẹ̀rẹ̀ láti Gansu títí dé etíkun gúúsù Manchuria.  Dáhùn ìbéèrè yìí ní ìbámu pẹ̀lú àyọkà náà: ìgbà wo ni wọ́n kọ́kọ́ kọ ògiri ńlá ti china? Ó dáa. Ẹ jẹ́ ká ronú. Ìmọ̀lára mi: 