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.
Lü Buwei
Lü Buwei (291–235 BC) was a politician of the Qin state in the Warring States period of ancient China. Originally an influential merchant from the Wey (衛) state, Lü Buwei met and befriended King Zhuangxiang of Qin, who was then a minor prince serving as a hostage in the Zhao state. Through bribes and machinations, Lü Buwei succeeded in helping King Zhuangxiang become the heir apparent to the Qin throne. In 249 BC, after King Zhuangxiang ascended the throne following the death of his father, King Xiaowen, he appointed Lü Buwei as his chancellor (相國) and ennobled him as "Marquis Wenxin" (文信侯). After King Zhuangxiang's death in 247 BC, Lü Buwei became the chancellor and regent to King Zhuangxiang's young son, Ying Zheng, who later became Qin Shi Huang (First Emperor of the Qin Dynasty).