四国と渡来の氏族：カモ族の足跡Clans Assimilated into Japan

Having completed my research along the San’in region on the Sea of Japan side, I swiftly crossed the Seto Inland Sea into Shikoku. During this research journey, I explored ancestral history, folk craft (mingei, 民藝), and kagura (神楽) in the San’in region, and conducted another investigation in Takahashi, a mountainous region of Okayama Prefecture. From there, I entered Shikoku for the latter part of my research, mainly investigating the western region of Sanuki Province (present-day Kagawa Prefecture), and have now moved into Awa Province (present-day Tokushima Prefecture).

The purpose of my research in Shikoku concerns the mysteries of ancient clans in Japan. Numerous ancient clans existed, and the prevalence of immigrant clans is astonishing. While most of these clans originated from China and Korea, some potentially extend as far as Central Asia and the Middle East, suggesting we may need to consider a broader scope of immigration.

Even just on this trip, numerous legends of immigrant clans were evident in Iwami Province (western Shimane Prefecture), deeply hinted at within myths from ancient texts like Kojiki and Nihon Shoki. Indeed, locals recount that due to ocean currents flowing directly from the Korean Peninsula to Iwami, people departing from Korea undoubtedly landed there. Walking along the coast of Iwami, one can even see numerous plastic items labeled in Korean washed ashore, illustrating contemporary currents.

However, because the account of the imperial lineage is tied to it, Japan’s historical narrative mostly recounts the arrival of immigrant clans along a single route, through northern Kyushu, and other sea routes have rarely been considered. The reasons are complex and bear directly on the imperial lineage, which I will discuss at an appropriate time.

Moreover, as I mentioned yesterday, local traditions from Inaba Province (present-day Tottori Prefecture) indicate that the ancient miko (巫女), or shrine maiden, Yakamihime was from an immigrant clan. Such information is rarely discussed publicly, and even I was unaware of it until yesterday, when an elderly woman at a shrine shared this story. Yet, detailed research reveals the fascinating truth that ancient Japan was composed far more diversely than anyone might imagine. The challenge remains whether this possibility will be accepted, as the Japanese populace might require considerable time to embrace such ideas fully.

Entering Shikoku as my research continues, the Yoshino River basin in Tokushima Prefecture distinctly demonstrates significant cultural differences between its western and eastern regions. These differences are rooted in the area’s historical development by different immigrant clans. Investigating this involves analyzing place names, shrines, deities worshipped, religious beliefs, and local legends. A surprising example for many readers is the trace left by the Kamo clan in western Tokushima Prefecture.

This is uniquely Japanese. Its exact origins are unclear, but from some point on, a distinctive account known as nichiyu dosoron (日ユ同祖論) has been handed down. Most readers will not know it, and this region has been regarded as one of the centers of that account. The clue here is place names. In Japan, place names speak of the oldest layers of the past.

An ancient clan that settled in this region took the name Kamo, written in kanji as 鴨, 賀茂, or 加茂. The name survives in place names across Japan, most famously in Kamigamo Shrine in Kyoto. Thus, like the Yakami clan, the Kamo clan was another significant ancient immigrant group. A crucial sacred site for the ancient Kamo clan was Mount Tsurugi in Tokushima Prefecture.

Mount Tsurugi, despite being a rugged mountain region, uniquely still has inhabitants living deep within its interior. According to well-known legends, most current residents descend from the Taira clan, who fled and hid in these mountains after being defeated by the Minamoto clan in the late 12th century, leaving numerous historical sites related to these tales. However, earlier periods positioned this area as a hidden sanctuary for the Kamo clan, who continued their religious practices in secret within the remote areas of Mount Tsurugi. Indeed, many legends related to the Kamo clan still permeate Mount Tsurugi, including locations atop the mountain believed to be sites of their ancient rituals.

From there, the Kamo clan gradually developed the middle basin of the Yoshino River plain, an area that still bears their legacy through a place still named Kamo district (加茂地区). During their settlement, they worshipped their ancestral deity, marking the origin of today’s Kamo Shrine. The main deity here is Wakeikazuchi, officially known as Kamo-wakeikazuchi, and the kanji 雷 in the name makes plain that this is a thunder deity.

Thunder deities appear widely among the oldest beliefs of the world. What the Kamo clan enshrined here was their own thunder deity, which took a Japanese form within the belief of the land and survives in shrine worship today. Indeed, part of the Kamo clan eventually migrated around the time of Heian-kyo (ancient Kyoto), settling near the present Kamigamo Shrine in Kyoto, an ancient shrine also dedicated to Kamo-wakeikazuchi, their thunder deity.

Heian-kyo’s city planning was based on an ancient Chinese divination method called kimon tonko (奇門遁甲). This method, used to read auspicious and inauspicious directions, has long been an esoteric practice passed down secretly among select groups in Japan. Heian-kyo featured specialists known as onmyoji who utilized these practices to create protective barriers and deploy guardian deities around Kyoto to ward off evil spirits.

This protective structure was based on the ancient Chinese concept called shijin soo (四神相応), involving four guardian deities: Seiryu, the Azure Dragon; Byakko, the White Tiger; Suzaku, the Vermilion Bird; and Genbu, the Black Tortoise. In Heian-kyo, the east was protected by Seiryu at the Kamo River and Yasaka Shrine, the west by Byakko at San’indo and Matsuo Taisha, the south by Suzaku at Ogura-ike and Jonan-gu, and the north by Genbu at Funaoka Hill and Kamigamo Shrine. These geographical features were believed to correspond with the four deities. Kamigamo Shrine, associated with the migrated Kamo clan, represented Genbu, a turtle entwined with a snake symbolizing mountains and winter—a clearly foreign, non-Japanese belief.

Additionally, Heian-kyo fortified its spiritual defense by placing temples like Enryaku-ji and Kurama-dera in the northeast, known as kimon (鬼門), the demon gate, believed to be the entry point for evil spirits according to onmyodo and feng shui. Legends abound in Kyoto, including the tale of Minamoto no Yoshitsune (1159-1189), who allegedly trained with tengu at Kurama Mountain, playing a pivotal role in defeating the Taira clan.

Beyond Kyoto, the Kamo clan expanded into Yamato (southern Nara Prefecture), later establishing Shimogamo Shrine. I do not trace the Kamo clan to a single origin; I want to look also at the possibility that they mingled and layered with others on the way to Japan, particularly in China. From the standpoint of belief, it is undeniable that the Kamo clan brought thunder deity worship to Japan.

Apart from the Kamo clan, there have been numerous suggestions of Persian clans immigrating to Japan. As previously mentioned, Seiganto-ji at Nachi Falls was founded by Dravidian monks. Observing kagura performances based on ancient legends in Iwami, one must also consider the legend of Xu Fu, a retainer of Qin Shi Huang who was ordered to find the elixir of immortality, reportedly dispatching 3,000 followers to Japan. In 1982, the discovery of Xu Fu Village in Lianyungang, Jiangsu Province, China, confirmed that such legends were not mere myths.

In Japan, Xu Fu’s main legendary landing sites are Iwami and Shingu in southern Wakayama Prefecture. In Iwami, local stories recount how Xu Fu’s group traveled in about 100 ships carrying around 30 people each, dispersing due to storms.

Such intriguing legends exist throughout Japan, but many details can only be uncovered by speaking directly to local elders, underscoring the necessity of extensive travel. Imagining the diverse, mixed origins of ancient Japan, I often wonder how a view that assumes one unchanging picture since ancient times became so dominant today.

My current research trip brought me to Tokushima for further investigation of other immigrant clans. The sheer number of immigrant clans assimilating into ancient Japan continually astonishes even me, a Japanese native. While fully unraveling this complexity will take considerable time, I will continue sharing updated insights bit by bit.