語られた歴史と沈黙の真実Spoken Histories and Silent Truths
Japanese history, for the most part, has been recorded as a narrative that justifies and strengthens the authority of the central government, with peripheral regions—except those that were subordinate or in allied relationships—receiving little attention. This is natural from the perspective of rulers who had discovered the power of documenting information and sought to consolidate their control, but with such a background, to assume that Japanese history provides a detailed account of the entire Japanese archipelago inevitably creates the problem of ignoring the histories of vast regions. In other words, if one regards only what is documented as absolute, the true nature of Japanese history cannot be seen.
This issue became even more problematic because Japan originally lacked a written language or a document-based culture. Even in the period from the Asuka era to the Nara era, when written records began to be developed through the influence of Chinese literati, this centralizing tendency continued to shape the historical record, leaving the fundamental problem unresolved.
For example, I travel to various regions to explore history while understanding the differences in nature between the Kojiki and the Nihon Shoki, but I am still struck by how much history remains untold. In fact, the Nihon Shoki quite faithfully follows the historiographical methods centered on the Chinese dynasties, and this tendency is easy to recognize. On the other hand, there is also the Kojiki, which employs a method of compilation that hints at a more pluralistic world, but both works reveal a pronounced centralist bias.
A particularly problematic case within this framework is the Japan Sea side. Looking back into history, it is clear that the Japan Sea coast was where significant development occurred in the Japanese archipelago, rather than the Pacific side as is often emphasized today. Yet in the present day, the major metropolitan corridor along the Tokaido—stretching from the Kansai region’s Kyoto and Osaka through Nagoya and Shizuoka to Tokyo—receives the bulk of attention, and indeed most major cities and industries are concentrated there. This is connected to the movements of the imperial court and successive shogunates that relocated from Yamato to Kyoto, then Kamakura, and eventually Edo. Establishing the political center on the Pacific coast had the advantage, from a security standpoint, of facing no other country across the ocean.
In contrast, the Japan Sea side had been a hub for exchange with the Asian mainland and the Korean Peninsula since ancient times, serving as both a point of trade and a window for tension. Contact with China, Russia, and the Korean Peninsula was frequent, and the flow of people and goods was likely heavy. For this reason, the central government had little interest in idealizing the Japan Sea side as the political center. Instead, the land they identified as ideal in ancient times was Yamato, which, during an era when invasions from the continent were a concern, was geographically one of the most difficult areas to penetrate—making it a logical choice.
As a result of these historical factors, from the reign of the emperors onward, the center of history was positioned along the Pacific coast, and in the latter half of the 20th century, the development of air travel made relations with North America—across the Pacific—increasingly important. Because the Japan Sea side lies close to Russia and China, the postwar diplomatic and security framework did not favor closeness with them, which further entrenched the tendency to disregard the Japan Sea region. However, a historical narrative that omits a comprehensive understanding of the Japan Sea side cannot accurately reflect ancient Japan.
Most of the history of the Pacific coast is based on the perspective of the Yamato court that emerged between the Asuka and Nara periods, and then extended through the frameworks of the Heian aristocracy and the warrior class. This limited historical viewpoint has been expanded to define the concept of “Japan” and has become entrenched over a long span of time. As a result, the eastern part of Japan has been largely neglected, and there are only a few surviving records of the central government’s attempts to invade eastern Japan. Among these, the Nihon Shoki stands out as one of the rare primary sources documenting these events.
In the Nihon Shoki, the first account of an expedition to the Tohoku region appears in a mythic form during the reign of Emperor Keiko, in the tale of the eastern campaign of Yamato Takeru (日本武尊). While this is heavily imbued with later creative embellishment, it serves as a symbolic narrative asserting that the court’s authority reached into Tohoku from early times. In actual history, the first full-scale expedition to Tohoku began in the mid-7th century during the reign of Empress Saimei, led by General Abe no Hirafu (阿倍比羅夫).
Hirafu commanded 180 warships, advancing northward along the Japan Sea coast toward the Akita and Tsugaru areas. According to the Nihon Shoki, the local Emishi (蝦夷) were so intimidated by Hirafu’s power that they offered to surrender, and he appointed a chieftain named Oga (恩荷) as the local ruler, thereby pacifying the region. He went on to form alliances with the Emishi of Tsugaru and Watarishima (渡島, present-day Hokkaido) and won a victory against the northern people known as the Mishihase (粛慎). This victory was staged in the imperial court as a grand political ceremony, with the presentation of captives and a lavish banquet, thereby projecting the court’s prestige. However, this is the account given by the Nihon Shoki, and it does not reveal the full reality of what occurred in northern Tohoku. This gap would later become a significant issue.
Through such expeditions, the Yamato court was able to claim nominal control over parts of Tohoku, establishing fortifications (城柵) and granting official titles to Emishi chieftains as part of an indirect rule strategy. In practice, however, many Emishi continued to resist, often rebelling, and cycles of submission and defiance repeated. In other words, the surrenders and allegiances depicted in the Nihon Shoki can be seen as idealized accounts of temporary truces or alliances, strongly shaped by the central court’s perspective and serving as political justification for the rulers’ actions. Nonetheless, this series of expeditions marked an early example of the Yamato court’s strategic focus on Tohoku, combining military and diplomatic measures to extend its influence, and it laid the groundwork for later campaigns against the Emishi in the Nara and Heian periods.
The history of the Tohoku invasions, as presented in the Nihon Shoki, frames them as a mission of the central government. Yet behind this lies the historical weight of the Japan Sea side and the Yamato court’s idealized state model, which was heavily influenced by the Chinese worldview. To neglect the Japan Sea side and understand ancient Japan solely through a Pacific-centered perspective is to greatly distort the reality. When reading the historical records produced by the central authority, it is essential to remain aware of their editorial intentions and limitations, and to incorporate viewpoints that have been left unspoken. This requires abandoning the entrenched notion of a single “center,” but because this has long been ignored in historical discourse, the comprehensive picture of Japan’s past remains obscured, leaving the study of history in a stagnant state.