War and Injury: The Emergence of Wound Medicine in Medieval Japan

The fourteenth century was a time of substantial, even revolutionary, change in Japan.¹ A broad cultural and political transition, from a reliance on the force of authority to a reliance on the authority of force, was propelled by an equally significant change in the nature of armed conflict, and for the first time Japan experienced the phenomenon of endemic national warfare. Previously military engagement had been an endeavor associated primarily with designated professionals (bushi) who engaged in short-term and geographically limited encounters. In the fourteenth century, however, it became a continuous, widespread, long-term enterprise in which many social groups participated.² This new warfare was prosecuted with sustained intensity (as highlighted by the frequency of suicide in the face of defeat and the starvation and occasional cannibalism of besieged warriors),³ and campaigning occurred year-round and in all weather conditions. All manner of weapons were used: the "traditional" items of sword, glaive, and arrow were augmented by spears, clubs, stones, rocks, boiling water, logs, and burning oil.

This new warfare environment was designed to inflict trauma on combatants—symbolic aspects of engagement or vestiges of "chivalry" were eliminated—and so injury was ever present. Indeed, a new calculus of reward for military service privileged evidence of bodily injury over mere presence on the battlefield. The battle service reports that were ubiquitous in the fourteenth century accordingly provide considerable information on wounds: number, how caused, where inflicted on the body, suffered by how many in a group, and sustained where and when.

It was also in this context of extended warfare that wound medicine—a surprisingly unstudied topic—emerged for the first time as a medical specialty.⁴ Prior to the fourteenth century, advanced medicine was largely in the hands of imperial court physicians, who drew from Chinese traditions. The medical problems to which they devoted their attention were not totally irrelevant to the treatment of trauma injuries, but the latter were not a primary focus of concern. From the fourteenth century, however, the situation changed, as evidenced in the appearance of the first Japanese texts devoted to wound medicine.

Although the authors of these works presumably drew in part from the existing body of general medical knowledge, the texts on wound medicine are notable for emphasizing information gained from practical clinical experience in treating those injured in battle. They show as well a shift to a new "interventionist" approach to medicine in place of the emphasis, fundamental to the tradition of Chinese medicine, on moderating internal constitutional imbalances, and a move toward greater reliance on "pharmaceutical" rather than "prayer" treatment. Consideration of the development of wound medicine can thus help illuminate not only the links between changes in medical technology and changes in the nature of warfare but also larger patterns in the history of Japanese medicine.

Wound Medicine Prior to the Fourteenth Century

At first glance it may appear surprising that, in a country whose history is distinguished by the longstanding existence of a warrior class, there is little evidence prior to the fourteenth century of battle injury being accorded any particular attention as a medical specialty. In fact, however, up to that time, armed conflict was a relatively infrequent phenomenon in Japan. A standing army was abolished in the 790s, less than a century after a Chinese-style imperial military system had been adopted, and, in the absence of external threat, the central government no longer involved itself directly in military activity. Internal security was maintained by a provincial elite that while cultivating martial skills and describing itself as a warrior class, acted mainly as land managers and local administrators within a framework of national civil administration. Warriors were not restive opponents of political authority.⁵

The armed conflict that did occur primarily took the form of brief skirmishes and ad hoc campaigns and was limited in geographic scope.⁶ Fighting was, if not entirely symbolic, rarely prosecuted to bloody conclusion. We do not encounter anything like nationwide fighting until the 1180s (when it resulted in the establishment of the first warrior government...