The Chu–Han Contention (206–202 BC) was an interregnum between the Qin dynasty and the Han dynasty in Chinese history. Following the collapse of the Qin dynasty in 206 BC, Xiang Yu split the former Qin Empire into the Eighteen Kingdoms. Two major contending powers emerged, Western Chu and Han, who engaged in a struggle for supremacy over China. Western Chu was led by Xiang Yu, while the Han leader was Liu Bang. Several minor kings also warred, but these were largely independent of the main conflict between Western Chu and Han. The war ended in 202 BC with total victory for Han, with Liu Bang soon proclaiming himself first emperor of the Han dynasty.

In 221 BC, the Qin state unified China by conquering the other six major states and established the Qin dynasty. However, the oppressive and extremely unpopular dynasty lasted only 14 years. In 209 BC, Chen Sheng and Wu Guang started the Dazexiang Uprising to overthrow the Qin dynasty.

Although the uprising was crushed, several others erupted consecutively over the next three years. Numerous pretenders to the former six states emerged, the most powerful being the Chu kingdom. The Chu general Xiang Yu won the support of many rebel leaders after his victory at the Battle of Julu, becoming the de facto leader of the insurgents and proclaiming himself "Hegemon-King of Western Chu" (西楚霸王). He ruled nine commanderies in the former Liang and Chu territories, with his capital at Pengcheng (彭城; present-day Xuzhou, Jiangsu).

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