From the 13th year of Daye in the Sui Dynasty to the first year of Wude in the Tang Dynasty (AD 617-618), the world was in chaos. Yang Guang was stranded in Jiangdu. Officials in various places took the opportunity to impose exorbitant taxes, and the victims were displaced in the middle and lower reaches of the Yellow River and along the Grand Canal. The "Wolf Howl Valley" at the junction of Qilu and Qilu is home to a special team of thieves who do not rob civilians but only rob officials and merchants. They have become a "stubborn disease" in the eyes of the government, but they are called "righteous thieves on the embankment" by the people.
