In 496 BC, He Lv, the king of Wu, sent troops to attack the State of Yue, and was defeated by the State of Yue. He Lv was seriously injured and died. Two years later, He Lv's son, Fu Cha, led an army to defeat the state of Yue, and Gou Jian, the king of Yue, was escorted to the state of Wu as a slave. After serving the King of Yue in humiliation for three years, Fuxi cleared his guard and sent him back to Yue.
In fact, Gou Jian did not give up revenge. On the surface, he obeyed the king of Wu, but secretly trained elite soldiers, strengthened political supervision and governance, and waited for an opportunity to fight back against Wu. Hardship can exercise the will, and ease will kill it. Gou Jian was afraid that he would covet the comfort in front of him and kill the will for revenge, so he arranged a hard living environment for himself. He sleeps at night without a mattress, just laying some firewood (called salary in ancient times) and hanging a gallbladder in the house. In order not to forget the shame of the past, he will taste the gallbladder from time to time.
In order to encourage the people to join the Queen and the people in the labor, Gou Jian made the State of Yue strong with the help of Vietnamese Qi Xin, and finally found the opportunity to destroy the State of Wu.