Introduction to Duke Huan's Prime Ministership: Duke Huan of Qi (716 BC - 643 BC) was the king of Qi in the Spring and Autumn Period of China (reigned from 685 BC to 643 BC). His surname was Jiang, his family name was Lu, and his given name was Xiaobai. During his reign, he appointed Guan Zhong to carry out reforms, select talents, strengthen military equipment, and develop production. He called on "respect the king and fight the barbarians", helped Yan defeat the Rong, rescued Xing and Wei, and prevented the Di tribe from attacking the Central Plains, and the country became strong. He united the Central Plains countries to attack Chu's ally Cai, and formed an alliance with Chu in Zhaoling (now northeast of Licheng, Henan). He also pacified the civil strife in the royal family of the Zhou Dynasty, made alliances with the princes many times, and became the overlord of the Central Plains.