The Battle of Changping (長平之戰) in 260 BC was a decisive victory of the state of Qin of China over Zhao during the Warring States Period. Even by today's standards it is one of the most lethal military operations in history, although a great majority of the Zhao soldiers were executed after battle instead of being killed in battle
Qin invaded the state of Han in 265 BC, with the intention of taking the Han province of Shangdang (上黨) somewhere in modern-day Shanxi province by cutting off all of its communications to the Han mainland. The Qin army ripped through Han territory – the main roads and fortresses across the Taiheng mountains were all captured by the Qin in four years. Shangdang was totally cut off from the rest of Han, and was poised to fall.
Han, in desperation, decided to give Shangdang to the neighbouring Zhao kingdom. Shangdang was a strategically important area to the west of Zhao; if it fell to Qin, Zhao mainland would be vulnerable to attack (which was why Qin wanted to take it in the first place). So King Xiaocheng of Zhao (趙孝成王) accepted the lands and sent Lian Po (廉頗) to deal with the threat posed by Qin. The two armies met at Changping (south of Shangdang) in 262 BC. On one side was the Qin army, led by Wang He (王齕), and on the other was the Zhao army led by Lian Po.
Lian Po, after looking over the Qin formations and after several minor defeats, decided that the only way to stop their attack was to wait it out. He built several fortresses in the summer of 260 BC and camped, waiting for the opposing army to go away. Despite this, the Qin army did manage to breach the Zhao walls once. Even so, they did not have the strength or equipment to break the Zhao defense, and the battle turned into a stalemate, lasting for three years
A New Strategy
The Qin had no intention of leaving. They sent spies to the states of Zhao and Han, ordering them to spread the word that Lian Po was cowardly and was too old to fight battles. The king, already dissatisfied with Lian Po's strategy, then decided to remove Lian Po and replace him with Zhao Kuo, the son of another famous Zhao general, Zhao She. At the same time, the Qin in the greatest secrecy replaced Wang He with the renowned general, Bai Qi.
Legend has it that on his deathbed, Zhao She told his wife never to let Zhao Kuo command an army. So Zhao She's wife, after hearing of Zhao Kuo's appointment as general, went up to the King of Zhao along with the minister, Lin Xiangru, and tried to persuade him not to appoint Zhao Kuo as general. The King refused, although Lady Zhao extracted a promise from king that the Zhao clan would not be punished should Zhao Kuo's command end in failure.
When Zhao Kuo assumed command in July 260 BC, the Zhao army (with reinforcements) numbered approximately 400,000 men. Zhao Kuo ordered the army to launch an invasion on the Qin camp. The Qin staged a feigned retreat, at the same time leaving two lines of ambush troops ready to block the Zhao army's retreat. The Zhao army pursued the enemy as far as the Qin fortress, while the Qin ambush forces, numbering 25,000 men, cut off the rear of the Zhao army and another 5,000 cavalry sealed off the Zhao fortress. The Zhao army was thus split into two parts and its supply lines were cut. Bai Qi then dispatched troops to make counter-attacks. With no hope of attacking or retreating, the Zhao forces built fortifications on a hill, preparing to wait for reinforcements
Since 295 BC, opportunism had dominated Zhao foreign policy; it had been shifting between Hezong (合縱) (alliance with the other five states to repel Qin expansionism) and Lianheng (連橫) (alliance with Qin to participate in its ascendancy). When King Zhaoxiang of Qin heard that Chu and Qi refused to assist Zhao, he hurried to Henei region (in Henan province, south of Changping), where he bestowed one grade of noble rank on the population and ordered all men over the age of 15 to go to Changping to block the Zhao food supply and reinforcements. The Zhao encampment on the hill was besieged for 46 days. On September, driven mad by hunger and thirst, the Zhao forces made several desperate charges down the hill, attempting to break out of the encirclement, but could not do so. Finally Zhao Kuo himself led his finest men into combat. He was shot down by Qin archers.
Surrender Of Zhao's Troops
The troops of Zhao thus surrendered. Bai Qi was afraid that the Zhao troops might eventually revolt, and the Shangdang people were against Qin's rule, so he devised some deception and had them all killed, sending only 240 of the youngest soldiers back to Zhao. In total, Zhao lost more than 450,000 soldiers in the campaign, while Qin also lost hundreds of thousands of men. The Battle of Changping therefore is listed among the most lethal battles in world history. Emperor Xuanzong of Tang saw and collected the human bones, built a temple on it. Today bones often dug out in the site.
More than three years of battle left both states financially and domestically exhausted. Qin recovered quickly, but Zhao did not.
Before the battle, Zhao was one of the most powerful of the Warring States. Although Zhao was saved after the battle from conquest, it did not recover from the defeat and was conquered by Qin about thirty years later. Thus with this victory, Qin had established military superiority over the other states. More campaigns and battles ensued, especially in the conquest of the state of Chu. Nevertheless no matter how bloody these military operations would be, Qin's final victory was guaranteed