The Zuo Zhuan, traditionally attributed to Zuo Qiuming of the Spring and Autumn Period, is a chronological historical book. Its original name was The Spring and Autumn Annals of Zuo. In the Han Dynasty, it was known as The Zuo Commentary to the Spring and Autumn Annals, The Inner Commentary to the Spring and Autumn Annals, and Zuo's. After the Han Dynasty, it was mostly called the Zuo Zhuan. It is collectively known as the "Three Commentaries on the Spring and Autumn Annals" together with The Gongyang Commentary and The Guliang Commentary. The Zuo Zhuan is a chronological work that records major historical events of the Zhou Dynasty and various vassal states over a period of 255 years from the 1st year of Duke Yin of Lu (722 BC) to the 27th year of Duke Ai of Lu (468 BC), and is highly regarded by later generations. It is one of the Confucian classics and has been studied by Confucian scholars throughout the ages. Together with The Gongyang Commentary and The Guliang Commentary, it is known as the "Three Commentaries on the Spring and Autumn Annals". It is often published together with The Spring and Autumn Annals and is included as one of the "Thirteen Classics". The Zuo Zhuan is voluminous and its content is diverse, covering many fields such as politics, economy, military, diplomacy, astronomy, geography, agriculture, medicine, customs, and literature, clearly presenting to readers the social culture and living forms of the Spring and Autumn Period and even more distant eras. In the chronological records of the twelve dukes of Lu, it not only explains the "Spring and Autumn writing style" used in The Spring and Autumn Annals but also records historical events of states other than Lu, such as Jin, Qi, Chu, Qin, Zheng, Song, Zhou, Wei, and even some small states, expanding the scope of states in The Spring and Autumn Annals. Through the dialogues of historical figures, the transcription of official documents, some details recounted by those who experienced historical events, and the comments of sages on various events, the narrative structure system of The Zuo Zhuan is formed. The Zuo Zhuan also quotes the Confucian classics The Book of Songs, The Book of Documents, The Book of Changes, and Confucian historical books through the mouths of historical figures. While narrating history, it helps readers interpret the words in these classics and expounds on the Confucian concept of governing the country. Therefore, The Zuo Zhuan can be regarded as both a classic and a historical work. In ancient times, it was said that Confucius wrote The Spring and Autumn Annals and Zuo Qiuming wrote the commentary for it. "What the first master said is the classic, and what the later master said is the commentary." This was the past tradition of Confucian classics, believing that The Zuo Zhuan was written by Zuo Qiuming. However, since the Tang and Song dynasties, after scholars of the Tang Dynasty broke the established view that Zuo Qiuming wrote The Zuo Zhuan, although scholars have different opinions on who the author of The Zuo Zhuan is, there has never been a clear conclusion about the author of The Zuo Zhuan, so people have to remain skeptical about this issue. As for the time when The Zuo Zhuan was written, "most scholars have a relatively similar view, believing that it was a product of the 4th century BC, that is, a work of the Warring States Period." However, as to what specific time in the 4th century BC, there are still many disagreements in the academic circle.