天皇以前の古代史：物部氏とナガスネヒコAncient History Before the Emperor

The Three Sacred Regalia (Sanshu-no-Jingi), said to be handed down within the Japanese Imperial Family, consist of the Yata no Kagami (八咫鏡, sacred mirror), the Kusanagi no Tsurugi (草薙剣, sacred sword), and the Yasakani no Magatama (八尺瓊勾玉, sacred jewel). According to mythology, these regalia were bestowed by Amaterasu, the ancestral deity of the imperial lineage, upon her grandson Ninigi. From this legend, the Three Sacred Regalia have historically symbolized the sanctity of the emperor and the legitimacy of imperial succession, and throughout history, numerous conflicts have revolved around these sacred artifacts. Emperor Jinmu, regarded as Japan’s first emperor, is also said to have inherited these regalia as a direct descendant of Ninigi, thus legitimizing his authority. However, it is essential to recognize that such narratives have an ideological aspect primarily aimed at bolstering imperial authority, and historically speaking, there may have existed other royal lineages transmitting different sacred regalia.

Notably, certain clans in ancient Japan maintained alternative traditions of sacred regalia directly linked to imperial legitimacy. Foremost among these was the Mononobe clan (物部氏). The Mononobe clan was one of the most influential clans in early Japanese history. However, with the introduction of Buddhism into Japan, a fierce conflict erupted in 587, known as the Teibi War (丁未の乱), considered one of the greatest ancient battles over dominance at the imperial court, fought between the Mononobe clan and the emerging Soga clan. The Mononobe, champions of the older order, were defeated by the Soga clan, who had gained considerable influence by bringing together new technologies and the people who carried them, and subsequently disappeared from historical prominence. Conventional Japanese history typically states that the Mononobe clan was annihilated at this juncture. Nevertheless, the term “annihilation” here is a critical keyword. In reality, not all lineages of the Mononobe clan perished during this conflict.

Indeed, the Mononobe main lineage, led by Mononobe no Moriya, who had dominated the imperial court at the time, was ultimately defeated after severe assaults on their stronghold located in Kawachi Province’s Shibukawa district (now around Higashiosaka City, Osaka Prefecture). However, historically, the Mononobe were not only in charge of rituals for the imperial family but also adept at military matters, controlling the imperial court’s armed forces, resulting in an extremely fierce battle. Mononobe no Moriya was killed by an individual named Tomi no Ichi (迹見赤檮), whose precise identity remains uncertain even today.

In ancient Japan, not only divine names but also personal names were recorded using Chinese characters, influenced by China, assigning kanji characters based on Japanese sounds. Hence, by examining names like Tomi no Ichi through phonetic perspectives rather than being misled by kanji alone, we can partially unveil historical contexts. Firstly, the term Tomi appears as 迹見, 登美, or 止美, recorded as the Tomi clan (迹見氏) in the Shinsen Shojiroku (新撰姓氏録), a genealogical record of ancient clans compiled under Emperor Saga’s command in 815, during the Heian period. Considering the nature of this work as a register of ancient clans, it suggests that the Tomi clan may have risen closer to imperial favor after their victory over Mononobe no Moriya two centuries prior.

According to the Shinsen Shojiroku, the Tomi clan is categorized as a descendant group from the Keno clan (毛野氏), listed as an imperial lineage branch (皇別氏族), recognized as a legitimate offshoot from Emperor Jinmu’s lineage. Yet, some theories persist that the Tomi clan may have originally been of immigrant origin. Another intriguing theory proposes that Tomi no Ichi might have initially belonged to the Mononobe clan itself. Indeed, tracing the sound “Tomi” back through history leads us even further back to the era before Emperor Jinmu’s enthronement. Specifically, it refers to the period when he was known as Kamu Yamato Iwarehiko (神倭伊波礼比古命) and undertook an eastern military expedition from the western frontier of Hyuga Province (now Miyazaki Prefecture) seeking utopia. At that time, near Mount Ikoma, located on the present-day border between Osaka and Nara prefectures, Kamu Yamato Iwarehiko engaged in intense battles. According to mythology, his opponent in these conflicts was named Nagasunehiko (長脛彦).

During that era, much of what is now the Osaka area was not yet land but rather an extension of Osaka Bay stretching far inland, necessitating a sea route to reach Ikoma Mountain and access Yamato (southern Nara Prefecture), their envisioned utopia. The tribal group guarding this strategic gateway to Yamato was precisely the one led by Nagasunehiko. Traces of this remain in how Nagasunehiko is referred to within mythology. In the Nihon Shoki, which was influenced by Chinese centralized mythological structures aimed at establishing unified emperor worship, his name is recorded as 長髄彦 (Nagasunehiko). However, the Kojiki, which lacks such centralized characteristics, refers to him as Tomi no Nagasunehiko (登美能那賀須泥毗古) or Tomihiko (登美毘古). Although ancient Japanese deity names are notoriously difficult to interpret, here it is safe to conclude that Tomi (登美) was the territory governed by Nagasunehiko.

Interestingly, memories of this ancient reality, predating written records, persist in local place names and beliefs, notably in an area known as Tomi, just beyond Ikoma Mountain on the Nara side. Today, these place names survive as Tomio (富雄) and Tomigaoka (登美ヶ丘), likely remnants meaning “heroes of Tomi” and “hill of Tomi,” respectively. From this area toward Ikoma Mountain, numerous places continue to preserve ancient myths, clearly indicating the existence of diverse deities and genealogies distinct from simplistic and unified imperial myths.

Indeed, Kamu Yamato Iwarehiko’s crossing of Ikoma Mountain in his quest to conquer Yamato ended in severe defeat at the hands of Nagasunehiko of Tomi. During this battle, Kamu Yamato Iwarehiko’s elder brother, Itsuse (五瀬命), suffered a fatal arrow wound inflicted by Nagasunehiko’s forces, forcing a retreat back to Osaka Bay and then southward toward Wakayama. This historical memory reflects that Emperor Jinmu did not simply conquer Yamato with ease. Due to this defeat, Kamu Yamato Iwarehiko’s forces became severely weakened, and upon arrival in Wakayama, Itsuse passed away. This illustrates the considerable strength of Nagasunehiko. However, it is crucial to recognize that ancient Japanese deity names did not represent independent individuals or kami, but rather symbolized specific tribal groups. In other words, while this narrative simplifies them as individuals—Kamu Yamato Iwarehiko, Nagasunehiko, and Itsuse—they were actually collective identities. Since realizing this fact in my research of ancient history, I have consistently emphasized it, although understanding it can be challenging. Thus, even Itsuse’s position as Kamu Yamato Iwarehiko’s elder brother symbolizes complex alliances or subordinate relationships among various tribal coalitions.

In fact, I have long researched Nagasunehiko out of personal interest and noticed something curious: traditions of Nagasunehiko extend beyond Yamato to remote regions across Japan. From a linguistic perspective, the name Nagasunehiko literally translates as the man with long legs, signifying a tribe of tall stature. Therefore, viewed from the perspective of Kamu Yamato Iwarehiko’s people, originally from distant Hyuga in Kyushu, the tribe occupying the strategic Tomi entrance to Yamato near Ikoma Mountain appeared notably taller and physically stronger. This trait subsequently became mythologized as Tomi no Nagasunehiko (登美能那賀須泥毗古).

To provide perspective, the average height of ancient Japanese people is estimated to have been around 158 cm for men and 149 cm for women among the Jomon population, and around 163 cm for men and 151 cm for women among the Yayoi people, whose roots trace to Northeast Asia. Kamu Yamato Iwarehiko’s forces likely conformed to this average height range. Hence, a tribe that appeared notably tall and formidable in military strength guarded the Yamato region prior to Kamu Yamato Iwarehiko’s arrival. Nagasunehiko thus holds a key to uncovering the buried aspects of ancient Japanese history lying outside the mainstream imperial lineage. While some people actively worship Nagasunehiko, I encountered an intriguing theory during my nationwide research into his historical reality—that Nagasunehiko was nearly two meters tall. To investigate this claim, I traveled to distant regions and, fascinatingly, discovered evidence supporting this fact, with ancient remains indeed indicating the existence of individuals approaching two meters in height.

This discovery greatly surprised me. Although not conclusive, it strongly suggests that Japan’s ancient past indeed included mysterious tribes absent from mainstream historical narratives. Nagasunehiko exemplifies this phenomenon, possibly explaining why the tribal group of Kamu Yamato Iwarehiko found it difficult, if not impossible, to achieve victory.

Mythology further reveals that Nagasunehiko was subordinated to yet another divine tribal entity—this deity is none other than Nigihayahi (邇芸速日命), the enigmatic deity closely associated with the Mononobe clan.