King Zhaoxiang of Qin
Reigning over 55 years, he was one of the longest-serving rulers during the Eastern Zhou Dynasty. Although making numerous policy mistakes during his later years, his aggressive territorial expansions were pivotal in consolidating the state of Qin as the dominant military powerhouse in the late Warring States period. It was the strategic dominance established during his reign that paved the way to Qin's eventual successful unification of China under his great-grandson, Ying Zheng.
Qin (state)
In 771 , the Marquess of Shen formed an alliance with the Zeng state and Quanrong nomads, and they attacked and captured the Zhou capital Haojing, killing King You of Zhou. Duke Xiang of Qin led his troops to escort King You's son King Ping of Zhou to Luoyi, where the new capital city of the Eastern Zhou Dynasty was established. In recognition of Duke Xiang's efforts, King Ping formally enfeoffed Duke Xiang as a feudal lord, and elevated Qin from an "attached state" (附庸, "fuyong") to a major vassal state. King Ping further promised to give Qin the land west of Qishan, the former heartland of Zhou, if Qin could expel the Rong tribes that were occupying the land. The future generations of the Qin rulers were encouraged by this promise, and they launched several military campaigns on the Rong, eventually expanding their territories to beyond the original lands lost by the Western Zhou Dynasty.