 Chu was finally conquered by Qin in 223 BC.At their peak, the armies of Chu and Qin combined numbered over 1,000,000 troops, more than the massive campaign at Changping between Qin and Zhao 35 years earlier.The excavated personal letters of two Qin regular soldiers, Hei Fu () and Jin (), records a protracted campaign in Huaiyang under general Wang Jian.