The Material Collection Process for the Tongjian

Writing a chronicle covering 1,300 years of history across 294 scrolls (juan) is not merely a writing task. It is first a materials problem. Sima Guang had to locate, evaluate, organize, and synthesize hundreds of sources, many of them fragmentary or contradictory, before he could write a single line of narrative. The Zizhi Tongjian is as much a triumph of information management as it is of historical writing.

The Scale of the Problem

Sima Guang was attempting something unprecedented: a single, continuous chronological narrative from 403 BCE to 959 CE. The official histories alone numbered in the dozens. The Shiji, the Hanshu, the Hou Hanshu, the Sanguozhi, the Songshu, the Nanqishu, the Weishu, the Suishu, the Jiu Tangshu, the Xin Tangshu, the Jiu Wudaishi, the Xin Wudaishi, and many more. Each of these was itself a massive compilation. Beyond the official histories, there were unofficial chronicles, personal memoirs, administrative documents, stone inscriptions, and the records of states that had never produced an official history at all.

The challenge was not just volume but contradiction. Two histories covering the same period might date the same event differently, attribute an action to different people, or evaluate the same person in opposite terms. Sima Guang had to choose, and his choices reveal his historical method.

The Three-Stage Method

Sima Guang developed what scholars now call a three-stage compilation method. First, he and his assistants created what he called the congmu (丛目), a detailed topical outline organized by year, listing every event from every source he could find. Each event entry included the source, the date as recorded in that source, and a brief note about contradictions with other sources. This was the raw data layer.

Second, he produced the changbian (长编), or “long draft.” This was a continuous narrative that wove together all sources into a single chronological account, preserving conflicting accounts and variant dates as footnotes and marginal comments. The changbian was deliberately long, including everything, with the intention of cutting it down later. Sima Guang’s assistant Liu Shu was primarily responsible for this stage.

Third, Sima Guang himself took the changbian and edited it down to the final text. He resolved contradictions, chose between variant accounts, tightened the prose, and added his evaluative commentary (the chen Guang yue or “your servant Guang says” sections). The result was the Tongjian itself, roughly one-third the length of the changbian from which it was cut.

The Team Behind the Work

Sima Guang did not work alone. He had a small team of specialist assistants, each assigned to a historical period where they had particular expertise. Liu Shu handled the pre-Han and Han sections. Liu Ban managed the Tang dynasty material. Fan Zuyu covered the later periods. The division of labor was based on each assistant’s familiarity with the sources for their assigned era.

This was not a case of Sima Guang hiring anonymous scribes. His assistants were accomplished scholars in their own right, and their contributions went beyond transcription into research, analysis, and drafting. The Tongjian is a collaborative work with a single editorial vision, and Sima Guang’s final editing is what made it cohere.

For more on the team, see the article on the assistant scholars and the parent article on Sima Guang’s life and work. The complete guide at Zizhi Tongjian overview provides the full context.

The three-stage method is worth studying because it solves a problem that has not gone away. Today’s researchers face the same challenge: too many sources, too many contradictions, too much material for one person to hold in working memory. Sima Guang’s solution was to separate collection from synthesis, and synthesis from final editorial judgment. Each stage has its own standards, its own purpose, and its own output.

The Longmu Boshi: The Auxiliary Catalog

Beyond the Tongjian itself, Sima Guang produced a companion volume called the Kao Yi (考异), or “Examination of Discrepancies.” This was originally embedded in the changbian as marginal notes, but Sima Guang separated it into an independent volume to keep the main narrative readable. The Kao Yi records the variant readings, contradictory dates, and alternative attributions that Sima Guang encountered, along with his reasoning for choosing one account over another.

The Kao Yi is, in modern terms, a methodology appendix. It lets readers see not just what Sima Guang concluded but how he got there. When two sources give different dates for the same battle, the Kao Yi presents both dates, assesses the reliability of each source, and explains the reasoning behind the choice. This level of transparency was rare in Song dynasty historiography and remains rare today.

How Sima Guang Evaluated Sources

Sima Guang’s source evaluation was not systematic in the modern peer-review sense, but it followed consistent principles. He privileged proximity: a source written closer to the event was generally preferred over a later one. He privileged official records for dates and administrative facts, but preferred personal writings for character assessment. He was skeptical of supernatural explanations and routinely omitted or rationalized accounts involving omens and prodigies that earlier histories had recorded at face value.

Most importantly, he was transparent about uncertainty. When the sources disagreed and the evidence did not clearly favor one side, he said so. The Kao Yi documents dozens of cases where Sima Guang chose the less dramatic account because it was better sourced, even when the more dramatic version was more widely known. This commitment to accuracy over readability is one of the qualities that distinguishes the Tongjian from popular histories.

What This Means for Modern Readers

The material collection process matters because it determines what the Tongjian can and cannot tell us. It is strong on political and military events, where official records are richest. It is weaker on economic history, social structure, and the lives of common people, where the sources Sima Guang had access to were thinnest. The Tongjian is a chronicle of courts and campaigns, not a social history, and that limitation is partly a function of what materials were available in the eleventh century.

For comparison with Sima Qian’s source use, see the Tongjian vs Shiji article. For the broader context of Sima Guang’s life and how he came to lead this project, see the parent biographical article and the article on his exile and the birth of his masterwork.

The Physical Production of the Manuscript

The Tongjian manuscript, when completed, was enormous. The final text ran to approximately three million Chinese characters across 294 scrolls. Before the age of printing, this meant hundreds of bound volumes of handwritten text. Sima Guang submitted the finished work to the emperor in 1084, along with a memorial describing the project’s scope and thanking his assistants.

The production process involved not just writing but copying, proofreading, and binding. Each scroll had to be physically assembled, and the complete set filled a significant shelf. Sima Guang noted in his memorial that after completing the project, only one complete copy existed, and he worried about its preservation. The court commissioned additional copies, but the physical fragility of the manuscript meant that for the first century of its existence, the Tongjian was accessible only to scholars with access to these copies.

The eventual printing of the Tongjian in the Southern Song dynasty transformed its reach. Once carved into printing blocks and reproduced, the work could be distributed to libraries, government offices, and private scholars across the empire. This is when the Tongjian became not just a court document but a standard reference for educated readers throughout China, Korea, Japan, and Vietnam.

The journey from raw sources to printed book took roughly a century: nineteen years of compilation, several years of copying and submission, and then the southern Song printing revolution that made wide distribution possible. The Tongjian is a reminder that major intellectual works are also logistical achievements, and that the gap between finishing a text and making it available to readers can be as significant as the gap between starting and finishing.

Frequently Asked Questions

How many sources did Sima Guang use for the Tongjian?

The exact number is not known, but scholars estimate he consulted several hundred sources, including at least seventeen official dynastic histories and numerous unofficial chronicles, personal writings, and administrative documents. The Kao Yi alone cites over 300 variant readings, each implying consultation of at least two sources.

What happened to the changbian (long draft)?

The complete changbian no longer survives. Sima Guang cut it down to produce the final Tongjian, and the long draft was not preserved as a separate work. However, portions survive embedded in later compilations, and scholars have partially reconstructed it from quotations in other Song dynasty texts.

Did Sima Guang use inscriptions and archaeological evidence?

He did use stone inscriptions when available, particularly for the Tang dynasty period where many commemorative steles were still extant. However, systematic archaeological method did not exist in the eleventh century, and material evidence played a much smaller role than textual sources in his compilation.

How long did the material collection take?

The entire project took approximately nineteen years (1066 to 1084 CE), with the first several devoted primarily to collecting and organizing sources. The congmu and changbian stages consumed the majority of the project timeline, while the final editing was relatively faster because it was an editorial process rather than a research one.

Can modern researchers replicate Sima Guang’s method?

The principle of separating collection, synthesis, and final editorial judgment is still used in systematic reviews and meta-analyses. The specific three-stage method can be adapted to modern research by using databases for the congmu stage, narrative synthesis for the changbian, and independent editorial review for the final version.

What is the Kao Yi and why is it important?

The Kao Yi (“Examination of Discrepancies”) is Sima Guang’s companion volume documenting his source evaluation. It records variant readings, contradictory dates, and his reasoning for choosing one account over another. It is essentially a methodology appendix that lets readers verify his decisions, and it set a transparency standard that few later Chinese historians matched.