During his term of office, the State of Qi became much stronger. The "Zuo Zhuan" records that in 660 BC, Guan Zhong urged Duke Huan of Qi to attack the small neighboring State of Xing which was under attack from Quan Rong nomads, a non-Chinese Rong tribes. Later, in 652 BC he advised the duke not to ally with a vassal ruler's son who wished to depose his father. Duke Huan often listened to Guan Zhong's sound advice such that his status amongst other Zhou vassal states rose. As a result, the duke came to be recognized as the first Hegemon or leader of the vassal alliance.