長平の戦い
By the end of the Warring States Period, Zhao was the only state strong enough to oppose the powerful Qin state. An alliance with Wei against Qin commenced in 287 BC but ended in defeat at Huayang in 273 BC. The struggle then culminated in the bloodiest battle of the whole period, the Battle of Changping in 260 BC. The troops of Zhao were completely defeated by Qin. Although the forces of Wei and Chu saved Handan from a follow-up siege by the victorious Qin, Zhao would never recover from the enormous loss of men in the battle.