There were two persons of the name Zhao Kuo 趙括, first, a dignitary and member of the house of Zhao 趙 in the state of Jin 晉 during the Spring and Autumn period 春秋 (770-5th cent. BCE), and second, a general of the state of Zhao during the late Warring States period 戰國 (5th cent.-221 BCE).
The first Zhao Kuo 趙括 (d. 597) was a son of Zhao Shuai 趙衰 (Zhao Chengzi 趙成子), a grand master (dafu 大夫) in the state of Jin. Zhao Kuo and his kinsmen Zhao Shuo 趙朔 (Zhao Zhuangzi 趙莊子), Zhao Yingqi 趙嬰齊, and Zhao Tong 趙同 were killed by Tu'an Gu 屠岸賈 in an internal quarrel for the succession of the throne. The Zhaos had killed the tyrant Duke Ling 晉靈公 and enthroned Duke Jing 晉景公, and Tu'an Gu, dominating Duke Jing, nearly managed to extinguish the house of Zhao.
The later Zhao Kuo 趙括 (d. 260 BCE) was a general of the state of Zhao and a son of general Zhao She 趙奢, Lord of Mafu 馬服君. Zhao Kuo was therefore also known as "Son of Mafu" (Mafuzi 馬服子). In 260, when the army of Qin 秦 attacked Zhao, the Qin general organized machinations at the court of Zhao by creating mistrust between King Xiaocheng of Zhao 趙孝成王 (r. 265-245) and his general Lian Po 廉頗. Lian Po was dismissed and replaced by Zhao Kuo, who had studied military treatises, but had not experience in the field. Zhao Kuo's mother and the aged general Lin Xiangru 藺相如 remonstrated against this appointment, citing Zhao She, who believed that his son would destroy the army of Zhao, but the King ignored their warnings.
Zhao Kuo exchanged his commanders and changed the tactics. Instead of continuing the defensive posture against Qin, he preferred offensive. In the battle of Changping 長平 (today's Gaoping 高平, Shanxi) in 260 BCE, Zhao Kuo's army was encircled by the Qin general Bai Qi 白起, and both armies entrenched themselves. When the army of Zhao ran short of supplies after 46 days of siege, Zhao ordered a sortie which was bloodily repelled. Zhao Kuo died by an arrow shoot, and his army surrendered soon. Historiographers report that Bai Qi buried alive 400,000 surrendering troops.