The allusion to breaking kettle and sinking boat comes from the Battle of Julu at the end of Qin Dynasty.
In 209 B.C., China's history witnessed the outbreak of a peasant uprising led by Chen Sheng and Wu Guang. After the sacrifice of Chen Sheng and Wu Guang, the two armies led by Liu Bang and Xiang Yu gradually grew stronger. In 207 B.C., Xiang Yu's rebel army fought against the main force of the Qin army led by Qin general Zhang Han in Julu (present-day Xingtai, Hebei Province).
Defying the enemy, Xiang Yu led his troops to cross the Zhangshui (a river flowing southeast from northeast of Julu). After crossing the river, Xiang Yu ordered his entire army to "all sink their boats, break their kettles and cauldrons, burn their huts, and hold their food for three days to show their soldiers that they would surely die, and none of them would return." In the battle of Julu, the Qin army was defeated, and Xiang Yu's soldiers shook the vassals.
Expanded Information
Process of the Battle--Breaking the Kettle and Sinking the Boat
In December of the third year of the Second Qin Dynasty (October 208 B.C.E. to September 207 B.C.E.), Xiang Yu led the Chu army to arrive at the Yellow River (a.k.a. the Zhangshui) in the southern part of Julu County, and immediately dispatched Ying Bu and General Pu to lead a 20,000-strong army of volunteers across the river to rescue Julu. After the two generals crossed the river and won a small victory in the first battle, Zhao general Chen Yu urged to advance again.
Then Xiang Yu led his army to cross the Yellow River (or Zhangshui), ordered them to burn down their houses and tents, and took only three days' food with them to show their determination to die if they did not win the battle, and rushed straight to Julu in a lightning speed, defeating Zhang Han's Qin army which was protecting the canon, and cut off the food route of Wang Li's army, and surrounded Wang Li's army.
It was Xiang Yu's determination and courage that inspired the generals. The Chu army encircled Wang Li's army, and all of them were so energized that they fought one by one, and became more and more courageous. After nine fierce battles finally repelled Zhang Han, captured Wang Li alive, killed the Qin general Su Jiao, the Qin general Shibuma raised the fire and burned himself, and the other Qin generals were killed and fled, and the Qin army besieging Julu deer disintegrated in this way.