The Zuo Zhuan has a reputation as "a masterpiece of grand historical narrative",[1] but its early textual history is largely unknown, and the nature of its original composition and authorship have been widely debated.

Most scholars now generally believe that the Zuo Zhuan was originally an independent work, composed during the 4th century BC, that was later rearranged as a commentary to the Annals.

[3] The Zuo Zhuan seems to have had no distinct title of its own during this period, but seems to have simply been called "Annals (Chunqiu)" along with a larger group of similar texts.

[4] Some modern scholars believe that the Zuo Zhuan was originally an independent work composed during the latter half of the 4th century BC—though probably incorporating some older material[5]—that was later rearranged as a commentary to the Annals.

[7] Alternatively, a number of scholars, beginning in the 18th century, have suggested that the Zuo Zhuan was actually the product of Wu Qi, a military leader who served in the State of Wei and who, according to the Han Feizi, was from a place called 左氏; zǔoshì.

[14] Kang's theory was that Liu Xin—who with his father Liu Xiang, the imperial librarian, was one of the first to have access to the rare documents in the Han dynasty's imperial archives—took the Discourses of the States and forged it into a chronicle-like work to fit the format of the Annals in an attempt to lend credibility to the policies of his master, the usurper Wang Mang.

[15] In the early 1930s, the French Sinologist Henri Maspero performed a detailed textual study of the issue, concluding the Han dynasty forgery theory to be untenable.

[15] The Swedish Sinologist Bernhard Karlgren concluded, based on a series of linguistic and philological analyses he carried out in the 1920s, that the Zuo Zhuan is a genuine ancient text "probably to be dated between 468 and 300 BC.

[17] The Zuo Zhuan recounts the major political, military, and social events of the Spring and Autumn period from the perspective of the State of Lu.

[18] It contains a variety of tense and dramatic episodes: battles and fights, royal assassinations and murder of concubines, deception and intrigue, excesses, citizens' oppression and insurgences, and appearances of ghosts and cosmic portents.

The entries follow the strict chronological format of the Annals, so interrelated episodes and the actions of individual characters are sometimes separated by events that occurred in the intervening years.

[19] The Zuo Zhuan's overarching theme is that haughty, evil, and stupid people generally bring disaster upon themselves, while those who are good, wise, and humble are usually justly rewarded.

[22] The Confucian principle of "ritual propriety" (禮; lǐ) is seen as governing all actions, including war, and to bring bad consequences if transgressed.

[22] However, the observance of li is never shown as guaranteeing victory, and the Zuo Zhuan includes many examples of the good and innocent suffering senseless violence.

[22] Much of the Zuo Zhuan′s status as a literary masterpiece stems from its "relentlessly realistic portrayal of a turbulent era marked by violence, political strife, intrigues, and moral laxity".

[24] Several of the most notable passages in the Zuo Zhuan describe succession crises, which seem to have been fairly common in China during the Spring and Autumn period.

[24] These crises often involved the "tangled affections" of the various rulers, and are described in a dramatic and vivid manner that gives insight into the lives of China's aristocratic elite during the mid-1st millennium BC.

[27] The chapter on the Battle of Chengpu contains the following ending comment: 君子謂是盟也信，謂晉於是役也，能以德攻。 The gentleman remarks: This alliance accorded with good faith.

[29] Several sections of the Zuo Zhuan demonstrate the traditional Chinese concept of 命; mìng; 'fate', 'destiny'—referring either to an individual's mission in life or their allotted lifespan—and attempt to illustrate how benevolent rulers ought to accept 'fate' selflessly, as in the story of Duke Wen moving the capital of the state of Zhu in 614 BC.

[33] From the Han dynasty (206 BC – AD 220) down to the present day, the Zuo Zhuan has been viewed as a model of correct, sophisticated Classical Chinese prose.

[34] The Zuo Zhuan′s great influence on the Chinese language is evident from the fact that it is the source of more chengyu than any other work, including the Analects of Confucius.

[35] The well-known Qing dynasty student anthology Guwen Guanzhi included 34 passages from the Zuo Zhuan as paragons of Classical Chinese prose, more than any other source.

[36] This era was highly significant in Chinese history, and saw a number of developments in governmental complexity and specialization that preceded China's imperial unification in 221 BC by the First Emperor of Qin.

[31] It was canonized as one of the Chinese classics in the 1st century AD, and until modern times was one of the cornerstones of traditional education for men in China and the other lands of the Sinosphere such as Japan and Korea.