Battle of Changping

Date	April, 262 BC – July, 260 BC
Location	Northwest of Gaoping, Shanxi
Result	Decisive Qin victory Qin unification of China becomes inevitable

Belligerents

State of Zhao

State of Qin

Commanders and leaders

Lian Po
Zhao Kuo †

Wang He (王齕)
Bai Qi

Strength

450,000

550,000

Casualties and losses

400,000

150,000

The Battle of Changping (長平之戰) was a military campaign that took place during the Warring States period in ancient China. It concluded in 260 BC with a decisive victory by the State of Qin over the State of Zhao, greatly weakening Zhao.

Qin invaded the State of Han in 265 BC to capture the Commandery of Shangdang, now in modern-day southeastern Shanxi province. Shangdang was strategically placed west of Zhao and its capture would open an invasion route into Zhao. Within four years, the Qin army isolated the commandery from the rest of Han by capturing the main roads and fortresses across the Taihang Mountains. Shangdang was poised to fall.

Rather than see Qin take Shangdang, Han offered the command to Zhao. King Xiaocheng of Zhao (趙孝成王) accepted and dispatched Lian Po and an army to secure the strategic territory from the encroaching Qin. The Zhao army met the Qin army, led by Wang He, in 262 BC at Changping, south of Shangdang. The Zhao suffered several minor defeats during initial confrontation with the Qin forces. Having assessed the enemy, Lian Po decided the only way to defeat the Qin was to wait them out, as Changping was much farther away from Qin territory than Zhao and thus keeping the army supplied would be much more taxing to the Qin.

The Zhao built several fortresses in the summer of 260 BC and then waited for the Qin to go away. The Qin managed to breach the defences once but did not have the strength or equipment to exploit it; nonetheless, the Qin refused to leave. A three-year stalemate ensued.

The Qin sent agents into Zhao and Han to spread rumours/accusations that Lian Po was too cowardly and old to fight. King Xiaocheng of Zhao was already dissatisfied with Lian Po's strategy. Lian Po was replaced by Zhao Kuo, son of the famous, deceased Zhao general Zhao She. At the same time, the Qin secretly replaced Wang He with the renowned general Bai Qi.

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Wikipedia