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)
According to the 2nd century  historical text "Records of the Grand Historian" by Sima Qian, the Qin state traced its origin to one of the Five Emperors in ancient times, named Zhuanxu. One of his descendents, Boyi, was granted the family name of "Ying" () by King Shun. During the Xia and Shang dynasties, the Ying split in two: a western branch in Quanqiu (present-day Lixian in Gansu) and another branch that lived east of the Yellow River. The latter became the ancestors of the rulers of the Zhao state.