Zhao, ancient Chinese feudal state, one of the seven powers that achieved ascendancy during the Warring States (Zhanguo) period (475–221 bce) of Chinese history. In 403 bce Zhao Ji, the founder of Zhao, and the leaders of the states of Wei and Han partitioned the state of Jin. The state of Zhao extended through northeastern and central Shanxi and southwestern Hebei. The state prospered for a time, seizing large areas of land within the territories of the states of Qi and Wei. It eventually became the strongest contender against the state of Qin, but its military strength was utterly destroyed by Qin in 260 bce; some 50,000 men were killed in battle, and most of the approximately 400,000 men who surrendered were slaughtered. The state of Zhao was finally annexed by Qin in 222 bce.