懷王之約：楚漢戰爭中劉邦對楚人勢力的爭奪

King Huai's Agreement：Liu Bang's Struggle for the Support of Chu People in the War between Chu and Han

楚漢戰爭是兩個楚人集團的戰爭，也是戰國晚期以降，秦楚大戰的重現。劉邦是以楚地的豐沛子弟為核心幹部，以抗秦為號召的起義者，「據秦伐楚」的形勢，以及倚賴秦地人力造成的成員異質化，對爭取楚人認同相當不利，讓劉邦與項楚爭取楚人勢力的正當性陷入困境。面對此一既要利用秦地人力、物力，又要紓解「據秦伐楚」的正當性危機的情況，劉邦最好的選擇是把形勢上的秦楚大戰，詮釋成兩個楚人集團的正統之爭。強化項羽背叛「懷王之約」以及弒義帝而自立的宣傳，就是劉邦把秦楚大戰詮釋成楚人正統之爭的最好策略。如此，就有利於劉邦陣營爭取楚人的認同，強化對楚人勢力爭奪的條件。歷來史家與論史者，誤讀了劉邦「懷王之約」的宣傳對象，自然也就無法正確理解劉邦宣揚「懷王之約」的目的。本文回歸楚漢戰爭是兩個楚人集團的戰爭，也是秦楚大戰的重現之特質，重新解讀劉邦大力宣揚「懷王之約」的企圖，分析此一策略的對象與目的。期望有助於對此一歷史公案的進一步理解 ，也期望對劉勝項敗的解讀，減少一些道德性的判斷。

The war between Chu and Han happened between two groups of the Chu people. Meanwhile, its background could be regarded as a reappearance of Qin-Chu war after the late Warring States. With people of Feng and Pei (both located in Chu) as central cadres, Liu Bang took “revolting against Qin” as his war cry and wanted to get the Chu people’s support. However, he had to occupy Qin’s land and rely on people from the Qin area to fight against Chu. Historians describe his situation as “occupying Qin and fight against Chu”. This situation did not appear to be good for Liu. Compared to Xiang Yu’s Chu, Liu seemed to have less legitimation to call for Chu people’s support. Facing such a dilemma, Liu tried to interpret the war as one for legitimation between two groups of Chu people rather than one that went between Qin people and Chu people. Emphasizing that Xiang Yu betrayed King Huai’s Agreement and killed Emperor Yi of Chu, was the best strategy for Liu to explain the war for legitimation and good for Liu to win Chu people’s support. Historians often misunderstood the target to whom Liu propagandize the King Huai’s Agreement. As a result, they couldn’t accurately explain why Liu propagandized it. This paper characterizes Chu-Han War to be one between two groups of Chu people, and also a reappearance of Qin-Chu war, and reinterprets Liu’s attempt to propagandize the Agreement, and analyzes the target and purpose of this strategy as well. This research should be helpful to further our understanding about this historical event, and to get rid of the moral judgments, often proposed by scholars when explaining Liu’s victory over Xiang.