title: History of the Great Wall of China
context: The history of the Great Wall of China began when fortifications built by various states during the Spring and Autumn (771–476BC)[1] and Warring States periods (475–221BC) were connected by the first emperor of China, Qin Shi Huang, to protect his newly founded Qin dynasty (221–206BC) 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.
question: When did construction on the Great Wall of China begin?
answers: during the Spring and Autumn (771–476BC)[1] and Warring States periods (475–221BC