BATTLE OF GUILING

The 'Battle of Guìlíng' (桂陵之戰) was fought between the states of Qí and Wèi in the Warring States period of Chinese history. In 354 BC, an army from Wèi was laying siege to Hándān city, the capital of State of Zhào. The next year, Zhào turned to Qí for help. Tián Jì and Sūn Bìn, acting as co-commanders of Qí, led an army to save Zhào. Judging that the best Wèi troops were besieging Hándān, Sūn Bìn led his army directly to the Wèi capital, Dàliáng. Wèi general Páng Juān was forced to return his soldiers back to Dàliáng. They were met and defeated at Guìlíng by Sūn's army and Páng Juān was taken prisoner.
This battle gives rise to a well-known proverb, "Besiege Wèi to rescue Zhào" (圍魏救趙), which is also included as one of the Thirty-Six Strategies.