King Zhaoxiang of Qin (Chinese: 秦昭襄王) (325–250 BC), or King Zhao of Qin (秦昭王), born Ying Ji (Chinese: 嬴稷), was the king of Qin from 307 BC to 250 BC. He was the son of King Huiwen and younger brother of King Wu.

King Zhaoxiang reigned as the King of Qin for 55 years, and was responsible for the state of Qin achieving strategic dominance over the other six major states. During his reign, Qin captured the Chu capital Ying in 278 BC, conquered the Xirong state of Yiqu in 272 BC, slaughtered a 450,000-strong Zhao army at Changping in 260 BC, and overthrew the Eastern Zhou dynasty in 256 BC. These aggressive territorial expansions and the strategic weakening of other rival states paved the path for Qin's eventual unification of China three decades later by his great-grandson Ying Zheng.

Prince Ying Ji was born in 325 BC to one of King Huiwen's more lower-ranked concubines, Lady Mi (羋八子). As a shu child, Prince Ji was given low priority in the royal line of succession, and as an underage child was granted no fief because the state of Qin employed a system of that demanded even princes to earn their own lands through national service. He was dispatched to the state of Yan at a young age to serve as a political hostage, a common diplomatic practice among vassal states throughout the Zhou Dynasty.

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