Duke Zhuang of Qin

Duke Zhuang of Qin (Chinese: 秦莊公; pinyin: Qín Zhuāng Gōng, died 778 BC) was from 821 to 778 BC the fifth ruler of the Zhou Dynasty state of Qin that eventually united China to become the Qin Dynasty. His ancestral name was Ying (Chinese: 嬴).

Duke Zhuang became the Qin ruler after his father Qin Zhong was killed in battle against the Rong tribes in 822 BC. King Xuan of Zhou gave Duke Zhuang and his four younger brothers seven thousand soldiers, and they defeated the Rong. King Xuan then awarded Qin the territory of Quanqiu (犬丘, also called Xichui, in present-day Li County, Gansu), formerly belonging to the senior branch of the House of Ying that was destroyed by the Rong, and Duke Zhuang moved the capital of the state from Qin (in present-day Zhangjiachuan County, Gansu) to Quanqiu.

Duke Zhuang had three sons. The eldest, Shifu (世父), refused the throne and would rather devote his life to campaigning against the Rong tribes in order to avenge the death of his grandfather Qin Zhong. Duke Zhuang died in 778 BC after 44 years of reign and was succeeded by his second son Duke Xiang of Qin. Duke Zhuang also had a daughter named Mu Ying (缪嬴), who in 777 BC became the wife of the Rong leader King Feng (豐王) in a political marriage.

Although the state of Qin grew much bigger and stronger after Duke Zhuang's victory against the Rong, Qin was still a minor state at the time and its rulers did not have any nobility rank. However, Duke Zhuang's son Duke Xiang would later be granted a formal nobility rank by King Ping of Zhou as a reward for protecting the king during the Quanrong invasion, and Duke Zhuang would also be posthumously granted the honorific title of duke.