Yang Hu (dates of birth and death unknown), with the clan name Yang and given name Hu, also known as Huo, was a household steward of the Ji Sun family. In the late Spring and Autumn Period (770-476 BCE), not only did the royal authority of the Zhou king continue to decline, but the ducal houses of various states also weakened. This shifted from the early Spring and Autumn Period's pattern of "rites and military campaigns issuing from the feudal lords" to "rites and military campaigns issuing from the high-ranking ministers" and "stewards (Peichen) controlling state affairs." "Peichen" refers to the servants of servants. For example, high-ranking ministers of a state who served as subjects to the feudal lord would call themselves "Peichen" to the Son of Heaven; similarly, the household stewards of these high-ranking ministers also referred to themselves as "Peichen" in relation to the feudal lord. During the Spring and Autumn Period, the State of Lu was governed by the "Three Huan families" (descendants of Duke Huan of Lu: the Meng Sun, Shu Sun, and Ji Sun families, who held state power). By the time of Dukes Zhao, Ding, and Ai of Lu, the power of household stewards rose, and rebellions among them frequently occurred. In the fourth year of Duke Zhao of Lu (538 BCE), Shu Niu, a steward of the Shu Sun family, placed Shu Sun Bao under house arrest and starved him to death, then plotted to kill Shu Sun Bao's two legitimate sons and installed the illegitimate son Shu Sun Nuo in power. In the twelfth year of Duke Zhao of Lu (530 BCE), when Ji Pingzi assumed power and failed to show proper respect to his steward Nan Kuai, Nan Kuai conspired to replace Ji Pingzi with Prince Nu: "I will expel the Ji family and return their property to the duke; you take his position, and I will serve as the duke's minister with Fei as my fief" (Zuo Zhuan, Duke Zhao, 12th year). When the plot was exposed, Nan Kuai rebelled with Fei and defected to Qi. From the fifth to the ninth year of Duke Ding of Lu (505-501 BCE), the Ji family steward Yang Hu dominated the government and effectively seized control of the state affairs of Lu.
The Yang Hu Rebellion was the longest-lasting and most influential uprising among the retainers of the State of Lu. Yang Hu’s power surpassed that of the "Three Huan Families" (the three major noble families of Lu) for three to four years. Originally a collateral branch of the Mengsun family, Yang Hu later became a retainer of the Jisun family and was highly trusted during the time of Ji Pingzi. After Ji Pingzi died and Ji Sunsi (Huanzi) succeeded him, Yang Hu was already a three-generation "elder" of the Jisun clan. During the funeral arrangements for Ji Pingzi, Yang Hu clashed with another Jisun retainer, Zhongliang Huai. Yang Hu demanded that the State of Lu’s precious jade, Yufan, be used to enshroud Ji Pingzi’s body, but Zhongliang Huai argued that this jade had been worn by Ji Pingzi when he performed rituals on behalf of the ruler during Duke Zhao’s exile, and since Duke Ding had now ascended, it could no longer be used. Yang Hu then colluded with the steward of Fei, Gongshan Buniu, intending to jointly expel Zhongliang Huai. Gongshan Buniu initially dismissed the idea, but later, after Zhongliang Huai showed him disrespect, he said to Yang Hu, "Go ahead and do it!" Yang Hu initiated the uprising, imprisoned Ji Huanzi and Gongfu Wenbo (Ji Huanzi’s cousin), and expelled Zhongliang Huai. In the tenth month of winter, Yang Hu killed Gong He Miao (a member of the Jisun clan), swore an oath with Ji Huanzi inside the Ji Gate, expelled Gongfu Wenbo and Qin Chuan (Ji Pingzi’s uncle-in-law), thoroughly eliminated opposing forces, and completely took control of the Jisun family. In the eighth year of Duke Ding of Lu (502 BCE), Yang Hu sought to eliminate the "Three Huan Families," planning to replace the Jisun family with Ji Wu, the Shusun family with Shusun Zhe, and the Mengsun family with himself. Yang Hu initiated the uprising during the winter sacrifice, but failed, fleeing to Guan (slightly northwest of present-day Ningyang County, Shandong) and Yangguan, where he rebelled from these two strongholds.