In Luo Guanzhong's "Romance of the Three Kingdoms", the color of respecting Liu Bei and belittling Cao Cao is clearly presented, with Liu Bei regarded as the legitimate ruler and Cao Cao as a usurper. Since ancient times, the debate over which is more legitimate between Wei and Shu has never ceased. After the establishment of the Western Jin Dynasty, Cao Wei was apparently regarded as a legitimate regime, for example, Chen Shou was originally a courtier of the Shu Han Dynasty, but after the fall of the Shu Han, he switched to the Western Jin Dynasty and wrote the Records of the Three Kingdoms. In the Records of the Three Kingdoms, the description of the Wei and Shu states is also unequal. In the Book of Wei, there are chapters such as "Emperor Wu Benji", "Emperor Wendi Benji" and "Emperor Ming's Benji", while in the "Book of Shu", there are only "Legends of the First Master". This shows that Chen Shou did not regard Liu Bei as an orthodox emperor. At the same time, Chen Shou used the term "ancestor" instead of the emperor's honorific title, implying that Liu Bei was only a prince of a place, not an emperor. When Chen Shou compiled the "Book of Wu", he also named Sun Quan's biography "The Biography of Wu Lord". In addition, in the Records of the Three Kingdoms, Liu Bei's team is called "Shu", but in fact, the national name of Liu Bei's team is "Han", which also reflects the official tendency of the Western Jin Dynasty. However, after the establishment of the Eastern Jin Dynasty, there was a tendency to respect Liu Bei and belittle Cao Cao, and even regarded Shu Han as a legitimate regime. Why is this the case?
First, in 220 AD, Cao Pi forced the Han emperor Liu Xiechan to cede the throne, and then established the Cao Wei dynasty, thus ending the Eastern Han Dynasty. In 265, Sima Yan also imitated this move, forcing the Wei Yuan emperor Cao Huanchan to relinquish the throne and establish the Western Jin Dynasty. Therefore, the Western Jin Dynasty needed to recognize Cao Wei's legitimacy in order to obtain its own source of legitimacy. However, the Western Jin Dynasty did not last long, and due to the Rebellion of the Eight Kings and the invasion of northern nomads, the Western Jin Dynasty officially perished in 317 AD. Sima Rui then fled to the south and established the Eastern Jin Dynasty. During the Eastern Jin Dynasty, people gradually changed their traditional concepts and began to accept the legitimacy of the status of Shu Han and Liu Bei emperors. Xi Chia, a famous historian and literary scholar of the Eastern Jin Dynasty, regarded the Shu Han as orthodox in his Spring and Autumn of the Han and Jin Dynasties, adopting the chronology of the Shu Han dynasty. Xi's view of chiseled teeth represents the view of the Eastern Jin court. In the Spring and Autumn of the Han and Jin Dynasties, Xi argues that Cao Wei usurped the throne of the Han Dynasty, and that the Sima clan was founded to "take revenge", i.e., the legitimacy of the emperors of the Western Jin Dynasty originated from the Han Dynasty. Therefore, the State of Jin prevailed over the State of Wei and inherited the traditions of the Han Dynasty. This view was very important in the Eastern Jin court, because in the early days of the Eastern Jin Dynasty, the regime was unstable, there were many powerful ministers, and the emperor lacked confidence in his legitimacy and lost control of the Central Plains, similar to the situation of the Shu Han. In order to consolidate its legitimate position and oppose the dynasty in the northern Central Plains, the Eastern Jin Dynasty began to advocate the legitimacy of the Shu Han. Both the Shu Han and the Eastern Jin Dynasty faced the dilemma of separating one side, but both also needed the Northern Expedition to the Central Plains. In addition, Liu Bei's emperorship did not come through the surrender of Liu Xie, the emperor of Han Xian, and Sima Rui was not designated as an heir by the Western Jin imperial family. It can be seen that Sima Rui needed to give Liu Bei orthodox status in order to enhance his own legitimacy.
Finally, all history is contemporary. Both the debate over the legitimacy of the Shu Han dynasty and the legitimacy of Liu Bei's status as emperor were influenced by the position of later generations. Therefore, after the establishment of the Eastern Jin Dynasty, for its own interests, it was isolated in the south of the Jiangsu, and if the legitimacy of Cao Wei was recognized, then did the former Qin, which occupied the northern central plains, become orthodox? Xi Chisel therefore spared no effort to insist on treating Liu Bei of the Shu Han dynasty as orthodox, connecting the legitimacy of the Jin state to the Han dynasty. The same situation occurred during the Two Song Dynasty. When Sima Guang, a minister of the Northern Song Dynasty, compiled the Zizhi Tongjian, he regarded Cao Wei as orthodox, but during the Southern Song Dynasty, he regarded Shu Han as orthodox. In short, although Luo Guanzhong wrote the Romance of the Three Kingdoms in the Ming Dynasty, during the Southern Song Dynasty, the story of the Three Kingdoms had been widely spread among the people, and showed a clear tendency to respect Liu Bei and belittle Cao Cao, which was also inherited and promoted by Luo Guanzhong.