Buddhist Cultural Exchange between Paekche and Ancient Japan: A Comparative Analysis of the Archaeological Remains from the Wooden Pagoda Site at Asukadera and Śarīra Reliquaries from Paekche Temple Sites

Abstract

This article provides a critical review of the results of the Asuka Historical Museum’s excavation of the Asukadera wooden pagoda site in Japan since 2015, and its implications for Buddhist cultural exchange in East Asia. The second section examines the Asuka Historical Museum’s categorization and scientific analysis of the beads, pearls, horse gear, earrings, gold and silver artifacts, mica, and śarīra containers. We assert that most objects excavated from the Asukadera wooden pagoda site are relics from the Asuka era (538–710), when the pagoda was first established in 593, and only a limited number of artifacts, such as the śarīra [relics] container, were added after the wooden pagoda was burned down in 1196. The third section compares the archeological remains from the Asukadera wooden pagoda site and the reliquary objects from the Paekche Wanghŭng-sa site (577) and Mirŭk-sa site (639), which have been conventionally considered to be its models. What the relics from these three historical sites have in common is that they include clothing accessories nobles wore as they participated in the Buddhist rituals of enshrining the śarīra in a wooden pagoda. However, some differences in the metallic craft items, such as crowns and belts, were still found between Paekche and Japan, which was due to the difference in costume styles in the respective countries at the time. Also, horse gear and lamellar armor unearthed from Asukadera sites was not found in Paekche temple sites, but is similar to earlier Japanese kofun (megalithic tumuli) grave goods, which provides evidence that as Buddhism was transferred to Japan from Paekche, it was not accepted in completely the same form.

1. Introduction

Asukadera 飛鳥寺 is Japan’s first full-scale Buddhist temple. It is also called Hōkōji 法興寺 or Motogang ōji 本元興寺. According to the Nihon shoki 日本書紀 (Chronicles of Japan, 720), Soga no Umako 蘇我馬子 (ca. 551–626), who had won the civil war with Mononobe no Moriya 物部守屋 in 587, commissioned the construction of Asukadera. Although Buddhists relics and architects arrived from Paekche in 588, construction of the temple did not commence until 592. The Asuka Great Buddha 飛鳥大佛 (Asuka daibutsu) was enshrined in the golden hall (main image hall) of the temple in 606, thus completing most of the central buildings (Figure 1) (McCallum 2009, pp. 42–45).

Japan’s Nara National Research Institute for Cultural Properties conducted three excavations of Asukadera from 1956 to 1957. The researchers found that when building the wooden pagoda and golden hall, the structural foundation was made using the “rammed earth” technique, or the method of constructing a stylobate of a two-floor building. In addition, the roof-tile patterns and production techniques for Asukadera are quite similar to those in Paekche temple sites (NNRICP 1958, pp. 47–48; Tsuboi 1985, pp. 48–52). However, at that time, few Paekche temple sites had been excavated, so it was unknown which specific temple served as a model for Asukadera.

Due to the increased excavation of Paekche historic sites in Korea, such as the wooden pagoda site at Wanghŭng-sa in Puyŏ in 2007 (PNRICH 2009), and the west stone pagoda at Mirŭk-sa in Iksan in 2009 (NRICH 2014), scholars have been able to affirm that Paekche’s temple construction techniques had a considerable influence on the building of Asukadera. In particular, the structural traces of buildings and other unearthed relics discovered in Puyŏ’s Wanghŭng-sa, constructed in 577, exhibit a significant affinity with Asukadera, which was established a decade later. Consequently, researchers from both Japan and Korea noted the possibility of the former temple being a model for the latter (Sagawa 2010, pp. 178–80; Lee 2022, pp. 7–12).

Written documents, such as the Nihon Shoki, indicate that when Paekche sent śarīra [relics] along with high-ranking officials and monks in 588, artisans and technicians with various specialized skills were also dispatched to aid in the construction of Asukadera. The architecture of Asukadera became an important symbolic representation of Asuka culture, not only because it was Japan’s first ever full-scale temple, but also because it served as the foundation upon which diverse systems of thought, new technologies, and the new culture of Buddhism were transferred from Paekche. This facilitated Japan’s growth into an ancient state. The abundant relics and historical remains found in Paekche’s Wanghŭng-sa and Mirŭk-sa sites serve as valuable research materials for Paekche history, but they also provide crucial clues that can shed light on the origins of Asukadera, the central hub of Asuka culture. The relics allow for a more detailed exploration of the innovations that Asukadera contributed to the formative process of the Japanese ancient state and culture.

From this perspective, the new materials found in the Wanghŭng-sa and Mirŭk-sa sites in Paekche have encouraged scholars to re-examine the existing materials from ancient Japanese temples. Since 2015, there has been a joint research project in progress for reorganizing the materials found deposited with the heart stone (shinso 心礎) of the wooden pagoda site kept at the Asuka Historical Museum. A central, axial shaft extends vertically through the center of any wooden pagoda, and the bottom of this pillar rests on the heart stone. The heart stone is empowered or sanctified by depositing small precious objects with the heart stone, which is situated under the foundation platform. The reconsideration and reclassification of objects deposited with the heart stone of the wooden pagoda at Asukadera, as a result of comparing them with materials buried with reliquaries inside Paekche pagodas, is the heart of this paper. It is a question of terminology. In this paper, following Japanese scholars, we refer to the objects buried with the heart stone as “pagoda deposits,” lit. “burial goods” (mainō-hin 埋納品). Similar objects have been excavated from early Korean pagoda sites, but these materials, discovered with the reliquary or śarīra container, have been conventionally described using the term “reliquary objects” (Kor. sari changŏmgu, Jpn. shari shōgongu 舍利莊嚴具). The primary purpose of this article is to analyze the process of the transmission of Buddhism to ancient Japan by highlighting the findings of this research group, which include rearranging and reclassifying the pagoda deposits from the heart stone of the Asukadera wooden pagoda site, as pursued by the Asuka Historical Museum in Japan, and comparing those materials with the reliquary objects unearthed in the Paekche temple sites of Wanghŭng-sa and Mirŭk-sa. The appropriateness of the term “reliquary object” for the materials unearthed with the heart stone is a secondary purpose of this paper.

2. Reorganizing the Pagoda Deposits Found in the Heart Stone of the Asukadera Wooden Pagoda Site

Asukadera is Japan’s first full-scale Buddhist temple in which the pagoda and altars are arranged in an orderly fashion. Early Japanese rulers recognized that Buddhism functioned as a governing ideology, closely intertwined with the throne, either strengthening the authority of the king, or helping to maintain diplomatic relationships and domestic affairs in many East Asian countries, such as the contemporary Korean kingdoms of Paekche (trad. 18 BCE–660 CE), Koguryŏ (trad. 37 BCE–668 CE), and Silla (trad. 57 BCE–935 CE), as well as the contemporary Sui dynasty (581–618) in China. Consequently, Japan actively pursued exchanges with neighboring states (Suzuki 2010, pp. 25–26). The construction of Asukadera was the result of a multifaceted exchange between the Japanese throne and that of Paekche. Monks and technicians necessary for the construction and management of the temple were invited from Paekche, marking a decisive opportunity for the formation of a new culture.

Japan’s Nara National Research Institute for Cultural Properties carried out three excavations of Asukadera from May 1956 to 1957. During the third excavation in 1957, an interior investigation was undertaken of the site of the square wooden pagoda with 12 m long sides (NNRICP 1958, pp. 17–18; McCallum 2009, p. 48). It revealed traces of the oldest enshrinement ritual of Buddhist śarīra in Japan, which corresponds to the Nihon shoki account of the first year of the reign of Empress Suiko (593) that “Buddhaśarīra [relics of the Buddha] were enshrined in the foundation of the stone pillar at Hōkōji on the 15th day of the first lunar month [21 February, 593] and the pillar was erected on the 16th [22 February, 593]” (Sakamoto et al. 1995, p. 173). However, investigation of the interior of the wooden pagoda site resulted in a somewhat complex appearance, as it not only revealed the relics buried at the time of construction in 593, but also included those re-buried after the fire in the Kamakura era (1185–1333).

A deeper examination of the interior investigation of the wooden pagoda site revealed a granite stone box unearthed from a point 60 cm below the ground level at the center of the pagoda (Figure 2a). The stone box consists of two pieces of stone, top and bottom. When the top stone was raised, there was a wooden case (outer śarīra container), and a large number of relics were excavated from the gap around the case. Inside the wooden case made of hinoki (cypress), there was a gilt bronze inner śarīra container, along with lampwork beads and amber. On the side of the wooden case is an inscription written in ink stating that Asukadera was destroyed by a fire caused by lightning on the 17th day of the sixth month of the seventh year in the Kenkyū era (1196), along with the names of the village official and six monks (Figure 2b).

This record corresponds to the content of the document called “A report on Buddhaśarīra excavated from under the wooden pagoda in the original Gangōji (=Asukadera)” (Hon Gangōji tōge kutsushutsu goshari engi 本元興寺塔下掘出御舎利縁起) that was submitted by the monk Bengyō of Tōdai-ji on the 20th day of the fourth month of the eighth year of the Kenkyū era [8 May, 1197], which reports that around 100 śarīra beads and gold and silver items were dug up from under the wooden pagoda on the 24th day of the third month [13 April] in 1197, after the Asukadera wooden pagoda burned down (Uehara 2023, pp. 218–20). Furthermore, the investigation revealed what was left out in Bengyō’s document; the fact that the śarīra excavated at the time was enshrined in a newly made śarīra container and reburied in the pagoda, along with parts of the reliquary objects that they already had.

In the excavation of the wooden pagoda site in 1957, the foundation, with each side measuring around 2.4 to 2.6 m, was found at the point 2.7 m below the current ground level (Figure 3). The contents of the square śarīra space, with a side length of 30 cm and depth of 21 cm, that was installed at the center of the foundational stone had been taken out in the religious excavation during the Kamakura era, so that no relics from the time of original construction were unearthed. Fortunately, from the eastern corner of the foundational pillar, which had not been excavated in the Kamakura era, a lamellar armor was unearthed, and from the southwestern corner, some horse gear and a large whetstone were all found intact in the positions in which they were initially buried. Thus, the materials unearthed from the Asukadera wooden pagoda site range from those that the time of burial can be specified from the excavation spot, to those that the time of burial cannot be identified as they were excavated from the disturbed layer (the pit excavated in the Kamakura era). The relics unearthed from this series of excavations are commonly called “artifacts buried in the foundation of the wooden pagoda”.

These artifacts appear to have been buried at two different periods; those buried in and surrounding the śarīra space in the foundation in 593, the first year of Empress Suiko’s reign (I: Artifacts buried in 593), and those newly buried after the 24th day of the third month in the eighth year of the Kenkyū era [13 April 1197] (II: Artifacts buried in 1197) (Figure 3,

Table 1. List of artifacts buried at the foundation of Asukadera wooden pagoda [Source: Based on (NNRICP 1958)].

(I) Artifacts Buried in 593
Item	Material	Number	Excavation Status
Lamellar armor 挂甲	Steel	1	①
Horse bell 馬鈴	Bronze	1	①
Snake-shaped ironware 蛇行狀鐵器	Steel	1	①
Large whetstone 砥石	Stone	1	①
Hemispheric metallic decoration 鍔付半球形金具	Gilt bronze	2	①
Earring 耳環	Gilt bronze, silver, bronze	29	①~③
Knife 刀子	Steel	11	①~③
Circular repoussé hardware 圓形打出金具	Gilt bronze	14	①·④
Pendant-type repoussé hardware 杏葉形打出金具	Gilt bronze	Over 28	①·④
Beads 玉類		Total 2382	①·③·④
Small glass bead 小玉	Dark blue	1493	①·③·④
	Blue	251	①·③·④
	Green	231	①·③·④
	Mauve	60	①·③·④
	Yellow	289	①·③·④
	Red	39	①·③·④
Magatama 勾玉	Jade	2	③·④
	Agate	1	③·④
	Glass	1	③·④
Tubular bead 管玉	Jasper	5	③·④
Multifaceted bead 切子玉	Crystal	2	③·④
Hollow bead 空玉	Silver	3	③·④
Gardenia seed-shaped bead 山梔玉	Silver	1	③·④
Gardenia seed-shaped bead 丸玉	Red agate	1	③·④
Lampwork bead 晴蛉玉	Glass	3	③·④
Mica flake 雲母片	Mineral	Multiple	②
Thin golden slab 金延板	Gold	7	②·③
Golden grain 金小粒	Gold	1	②·③
Thin silver slab 銀延板	Silver	5	②·③
Silver grains 銀小粒	Silver	7	②·③
Ornamental hairpin 步搖	Gilt bronze	Over 146	③·④
Gilt bronze bell 金銅鈴	Gilt bronze	7	④
Amber slab 琥珀片	Mineral	200	④
Fragment of cover stone 蓋石片	Tuff	4	②
(II) Artifacts buried after 1197
Śarīra container 舍利容器	Gilt bronze	1
Śarīra container outer box 舍利容器 外箱	Hinoki (wooden)	1
Oil lamp cover 燈明皿	Earthen	1

). Because the report mentions that “these artifacts have not yet been sufficiently organized and have many issues to be examined again in the future” (NNRICP 1958, p. 27), it is not easy to strictly distinguish between the two groups (Figure 4a). However, in reorganizing the artifacts at the Asuka Historical Museum after 2015, we have come to be able to somewhat classify the artifacts from the original construction of Asukadera.

First of all, the beads should be examined. The report records that some beads were found along with the gilt bronze śarīra container in the wooden box, and that beads filled up the gap between the wooden box and the stone box (NNRICP 1958, p. 17). A reorganization and scientific analysis of these glass beads were conducted, meticulously checking and verifying around 3000 pieces of glass beads and fragments.

According to the compositional analysis results of the glass beads, the beads are divided into three types: first, small glass beads that are considered to be from either India or Southeast Asia; second, small glass beads made of plant ash 植物灰, that are considered to be from Mesopotamia or Central Asia; third, glass beads that are of secondary production using these small glass beads or broken pieces. Since all three types of glass beads had already been introduced to Japan in the Kofun era (ca. 350–600), the glass beads excavated from the foundation of Asukadera wooden pagoda were all judged to have been buried at the time of constructing the temple. Also, considering the fact that there were small glass beads among the reliquary objects unearthed from the Wanghŭng-sa wooden pagoda site (577), which had similar shapes and chemical compositions (PNRICH 2009, pp. 241–42), it is assumed that the small glass beads that had been introduced to Paekche from the West in the late 6th century had been transferred to Asukadera along with Buddhaśarīra in 588 (Ishibashi and Tomomi 2016, pp. 12–13).

During the process of reorganizing the artifacts, it was newly ascertained that the 14 white and opaque small beads, the material of which had been considered unknown until now, were pearls (Figure 4b) (Tamura 2018, pp. 58–59). Pearls are among the seven treasures 七寶 in Buddhism, and about 800 pearls have been excavated from the western stone pagoda of Mirŭk-sa (NRICH 2014, pp. 142–43). The pearls from Mirŭk-sa site have a radius of approximately 4mm, round with a hole in the center; they are assumed to be gems used in necklaces, hair accessories, and diadem ornaments (Sin 2016, pp. 38–40). Since there were barely any pearls excavated from Japanese ancient burial mounds, it appears that the artifacts buried in the wooden pagoda include accessories that are different from those of the Kofun culture.

Horse gear, such as a horse bell 馬鈴, and snake-shaped ironware 蛇行狀鐵器, was also re-examined. The horse bell made of bronze is cast in the shape of a ball, with patterns decorating the bottom side (Figure 4c). Similar horse bells have been excavated from the ancient burial mounds of the Korean state of Kaya (trad. 42–562), but none have borderlines or decorations on the ball. The snake-shaped ironware also has similarities with artifacts from the ancient burial mounds of Kaya, in its formal characteristics and use method. However, considering that the kingdom of Kaya collapsed in 562, it seems highly possible that the horse gear excavated from the wooden pagoda site had been manufactured in Japanese workshops that crafted Kaya horse gear (Isahaya 2015, pp. 47–49).

Among the artifacts buried there were at least 11 knives 刀子, but none were unearthed intact at the original position. The size and shape of the knives is not different from those of burial goods from the Kofun era. One silver knife (a knife decorated with silver) was unearthed, but most are plainly shaped with wooden handles covered with leather. Among the reliquary objects unearthed from Wanghŭng-sa, eight knives were found, and among those unearthed from Mirŭk-sa, seven were found. Both plain and fancy types of knives were found. Since the knives excavated from Asukadera have leather handles and sheaths that were produced since the early Kofun era in Japan, it seems highly possible that they were made in Japan (Ishibashi et al. 2016, pp. 20–21).

Although it is difficult to count the exact number of earrings due to some broken pieces, an analysis was conducted for 29 of them. Following their materials, a total of six types and 16 sets of earrings were classified as follows: first, nine pieces (five sets) made in bronze and amalgam-plated (gilt bronze); second, four pieces (two sets) in twisted gilt bronze; third, six pieces (three sets) made in bronze with thin gold slabs stuck on the surface; fourth, two pieces (one set) made in bronze with thin silver slabs stuck on the surface; fifth, one piece (one set) made in silver with thin gold slabs stuck on the surface; sixth, seven pieces (four sets) made in bronze. Those excavated from the original place only include the four pieces found in the southwestern corner in the upper layer of the foundation, including the three pieces in bronze and one piece made of bronze with a thin gold slab stuck on the surface.

Gilt bronze earrings unearthed from the ancient burial mounds (kofun) of Japan show a trend of large earrings with a radius of around 3cm and thickness of over 6mm in the mid-6th century, then becoming smaller in the early 7th century. Since the earrings excavated from Asukadera are large, it appears that they were those made and circulated domestically in Japan in the late Kofun era (Ishibashi et al. 2017, pp. 55–57). Yet, considering that not only earrings decorated with pendants, such as bells or heart-shaped leaves, but those made in silver were also found among the reliquary objects unearthed at Wanghŭng-sa (PNRICH 2009, pp. 60–63), we cannot completely exclude the possibility that the silver earrings among those excavated at Asukadera were made in Paekche.

As for the silver and gold items, seven thin gold slabs 金延板, one grain of gold 金粒, five thin silver slabs, and seven silver grains were unearthed, though not from the original burial positions (Figure 5a). These gold and silver goods are not found among the Kofun burial goods of the era, while thin gold and silver slabs in similar forms have been excavated among the reliquary objects of the Wanghŭng-sa wooden pagoda and the Mirŭk-sa west stone pagoda (639). Therefore, it seems likely that these artifacts were also transferred from Paekche (Isahaya et al. 2018, p. 55).

It is remarkable that mica, with a gross weight 1g, was found in the lowest layer (just above the foundation) of the pit excavated in the Kamakura era (Figure 5b) (Ishibashi 2021, pp. 20–21). It is assumed that burying mica in tombs in ancient East Asia was related to the belief in gods and immortals or Taoism, because a crown cap was excavated from Wanghŭng-sa wooden pagoda with flower-shaped ornaments made of mica (PNRICH 2009, pp. 60–63), and this artifact is also made of a material that reveals the close relationship between Asukadera and Paekche.

On the one hand, a basic investigation is being conducted on the gilt bronze inner container and wooden outer container for śarīra, that were buried in a stone box newly made in the Kamakura era (Figure 2b). Although the inner container for śarīra cannot be opened for inspection, an x-ray CT scan has shown that more than two types of doughnut-shaped components are inside. From the shape, it can be assumed that they are glass beads like those excavated from around the area, but scholarly interpretations are still in progress (Ishibashi et al. 2023, p. 8). On the other hand, the gilt bronze inner container for śarīra has a unique shape for śarīra containers from the Kamakura era, so scholars suggest the possibility of it being made in a special shape, combining knowledge of Buddhastūpas (pagodas) from the western regions (India and Central Asia) and the image or style of the original śarīra container that was buried in the Asuka period (Ishibashi et al. 2023, p. 9).

3. Japan’s Reception of Buddhism Seen through a Comparison of Reliquary Objects Unearthed from Asukadera and Paekche Temple Sites

Whether we can consider the entirety of the artifacts buried with the heart stone of the Asukadera wooden pagoda examined in the previous section as “reliquary objects” in a strict sense remains controversial. However, the śarīra newly made and added in the Kamakura era is not acknowledged in the least. Except for the newly made śarīra container and the oil lamp cover that was inside the śarīra space in the foundation, there is a high possibility that all artifacts, including those with uncertain burial positions, were buried during the series of rituals that includes the śarīra burial that was held in January, 593.

The artifacts can largely be divided into two groups. First is the group of artifacts that are in common with the burial goods in the ancient burial mounds of the same period, including the lamellar armor, horse gear, earrings, knives, ornamental accessories such as dangling hairpins, and various jade beads. It has been emphasized from early on that these items of relics have a lot in common with the burial goods of the ancient burial mounds (Tsuji 2006, pp. 187–90; McCallum 2009, p. 66). The other group consists of thin gold and silver slabs and grains, pearls, and mica, items that are not buried in Japanese ancient burial mounds and are not large in number. It is indeed understandable why Tsuboi Kiyotari, who excavated the heart stone of the wooden pagoda, reflected as follows: “I felt as though I had excavated a stone-chamber tomb and was organizing the burial goods from the tomb” (Tsuboi 1985, p. 35).

As clearly verified in the literary record and excavated materials, scholars presume that there had been a direct transfer of techniques from Paekche in the construction of Asukadera, which is the first Buddhist temple in Japan to have a full-scale temple layout, and increasingly more archaeological evidence supports this presumption (AHM 2013, pp. 28–39). Although clues about the śarīra or śarīra containers from the time of construction are yet to be found, they should be seen as items shipped in from Paekche in 588. Naturally, it is also highly likely that items from Paekche were included among the reliquary objects. Thus, we compared the artifacts excavated from the Asukadera wooden pagoda site with the reliquary objects recently unearthed one after another from Wanghŭng-sa (buried in 577) and Mirŭk-sa (buried in 639) and organized the similarities and differences to examine the topic of Buddhism being accepted in the Japanese archipelago.

First to be examined is the similarity of the relics. Both Asukadera and Wanghŭng-sa had put a large stone with a śarīra space in the underground center of the stylobate of the wooden pagoda, and the śarīra space had been covered with stone lids. A certain number of heart stones have been discovered in the wooden pagoda sites of ancient Japanese temples that have śarīra spaces that are either underground or above-ground. This method of śarīra burial has not been found in any case in China, thus showing a high possibility that it was created in Paekche (Sagawa 2010, pp. 168–70).

Next, turning to the artifacts, we found that among those buried with the heart stone of the Asukadera wooden pagoda, those that are not included in Kofun burial goods, such as thin slabs and grains of gold and silver (Figure 5a), were similar to those excavated from Wanghŭng-sa and Mirŭk-sa (Figure 6). It was also common to both the Asukadera and the Paekche temples to bury large amounts of jewels, including small glass beads. Many glass beads being unearthed from among the reliquary objects is certainly not limited to Paekche or Japan. A large number of jewels was found in Hetaoyuan 核桃園 (Walnut Garden) building site no.1, which is presumed to be the Dazhuangyan Temple 大莊嚴寺 of the Northern Qi 北齊 dynasty (550–577) in China (IACASS 2016, pp. 575–81).

What is more remarkable here is the bilateralism between Paekche and Japan. As mentioned above, included among the small glass beads found in Asukadera were those with similar shapes or chemical compositions to those found in Wanghŭng-sa (Ishibashi and Tomomi 2016, p. 12). Although comma-shaped jade gemstones (magatama 曲玉) were unearthed from Asukadera, Wanghŭng-sa, and Mirŭk-sa, jade (hisui 翡翠) is not produced on the Korean peninsula. Therefore, it is assumed that the gemstones were at least harvested around Itoigawa 糸魚川, in Niigata, Japan.

Scholars acknowledge a high level of commonality among the pagoda deposits from the heart stone of the Asukadera wooden pagoda and the reliquary objects of contemporary Paekche, and this similarity is the basic result of the Buddhaśarīra being transferred from Paekche to Japan and the śarīra enshrinement ritual being introduced together. However, as we look deeper, there are not only things that were brought from Paekche to Japan, but also those that were taken to Paekche from Japan. This is an important point that should not be overlooked when considering Japan’s exchanges with Paekche through Buddhism.

We next examined artifacts that are similar yet a little different. A total of eleven knives were found in the heart stone of the Asukadera wooden pagoda, and several knives were also excavated among the reliquary objects of the Wanghŭng-sa, and Mirŭk-sa sites. The knives are assumed to be goods carried by nobles, then donated and offered as they participated in the ritual of enshrining the śarīra in the wooden pagoda (Chu 2018, pp. 57–60), and this seems to have been from the influence of Paekche. Yet, what needs to be carefully considered here is the material. There are knives with leather handle sheaths or handles with staghorn ornaments among those excavated from the Asukadera wooden pagoda, and these are characteristics that are not found in either Wanghŭng-sa, Mirŭk-sa, or the entire Korean peninsula, but are generally seen in the knives excavated from Japanese ancient burial mounds. It is also important that the “wooden material of coniferous tree considered to be hinoki” was verified among the wooden handles of knives through a micro-focus x-ray CT scan (Ishibashi et al. 2016, p. 19). If it is indeed hinoki, it means that the handles were made with wood unique to Japan, that is not grown in Korea. Therefore, although the act of including knives in the reliquary objects can be seen as an influence from Paekche, the knives excavated from the Asukadera wooden pagoda are not imported from Paekche, but crafted in Japan.

Finally, we investigated the differences. Among the artifacts excavated from the heart stone of the Asukadera wooden pagoda, there is pendant-type repoussé hardware made of gilt bronze 杏葉形 打出金具 (Figure 7a). When first unearthed, the usage of these artifacts was completely unknown. Yet, as gilt bronze oval- and knife-shaped 劍菱形 ornamental hardware, with the size and shape almost the same as that of an Asukadera artifact, was unearthed from Fujinoki Kofun 藤ノ木古墳 from the late 6th century in Nara, Japan, in the 1980s, it was revealed to possibly be the ornaments for the mizura hairstyle 美豆良 (NPKARI 1995, pp. 267–68). Though there are various theories about the origin of mizura, it is considered the general hairstyle of men in the Kofun period, as observed in the form of the man-shaped haniwa (terracotta clay figures used as burial mound decoration). It is assumed that the gilt bronze oval- and knife-shaped ornamental hardware was an ornament in the form of a headband to decorate the forehead, worn with the tip pointing upward (Figure 7b), or worn by threading small glass beads and hanging them from the mizura ornament (Figure 7c) (Tsuji 2006, pp. 188–89; AHM 2013, pp. 32–34).

The Fusō ryakuki 扶桑略紀 (an abbreviated account of Fusō [Japan]), written in the late Heian period (794–1185), reports that High Minister Shima 嶋大臣, and over 100 participants, all combed their hair and wore Paekche clothing on the day of enshrining the Buddhaśarīra and erecting the pillar of the Asukadera wooden pagoda, and that all who saw the scene rejoiced (Kōen 1932, p. 38). Although late, this is considered a reliable record (Suzuki 2010, pp. 32–33). Thus, when the participants, including Soga no Umako, performed the ritual of erecting the pillar, they had presented themselves with Paekche-style hair and costumes. However, there was no ornament found in the Asukadera wooden pagoda site like the silver flower-shaped hat ornaments and mica decoration (Figure 8a,b) that can be found among the reliquary objects of Paekche’s Wanghŭng-sa or Mirŭk-sa. In Wanghŭng-sa or Mirŭk-sa, though with some differences, hat ornaments and belt decorations were found together (Yi 2009, pp. 65–69), and their shapes were completely different from the hat ornaments unearthed from Asukadera (Figure 8d).

The similarities of lamellar armor or horse gear among the buried artifacts in the Asukadera wooden pagoda with the Kofun burial goods of then-contemporary Japan have been emphasized until now (Tsuboi 1985, pp. 33–38; Tsuji 2006, p. 190). However, since these artifacts are ornamental items for people and their horses, we can interpret them with the same criteria as clothing. The similarities between the reliquary objects found in the Asukadera wooden pagoda and Kofun burial goods are likewise identified in Paekche. The reliquary objects unearthed from Wanghŭng-sa and Mirŭk-sa sites are quite similar to the ornaments buried in Muryŏngwang-nŭng (Tomb of King Muryŏng, 523) in Kongju, or the ancient burial mounds of Paekche in the Sabi era (Yamamoto 2010, pp. 147–51). Considering the fact that quite a large portion of these artifacts were personal furnishings worn on the body, the differences shown in the reliquary objects of Asukadera, Wanghŭng-sa, and Mirŭk-sa can be understood as originating from differences in the “attire” worn by the people who attended each of the śarīra enshrinement rituals.

When performing the rituals to enshrine the śarīra and erect the pillar for the wooden pagoda in 593, Soga no Umako sought to emulate the Buddhist culture and institutions of Paekche by wearing Paekche-style clothes and imitating the Paekche way of Buddhist ceremonies. This allowed Japan to assert, both internally and externally, that the cultural and institutional norms associated with Buddhism were rooted in those of Paekche. Although Asukadera was heavily influenced by Paekche temples, it also exhibits subtle differences. The materials among the artifacts excavated from the foundation of the wooden pagoda that are different from those of Paekche are associated with Kofun burial goods from the previous period, and the ornaments worn by nobles who attended the rituals also display variations. These differences shed light on the evolving nature of Paekche Buddhism as it entered Japan at the time.

Paekche had been largely influenced by the Chinese Northern and Southern Dynasties in not only the construction of temples, but also the method of enshrining śarīra (Chu 2018, pp. 66–74). In 538, Liang Emperor Wu (r. 502–549) performed the ritual of enshrining śarīra in a container composed of gold, jade, the seven treasures, and a stone case at Changgansi 長干寺 in Jiankang (present-day Nanjing), and the royals and nobles who attended the ritual made a large number of offerings with gold, silver, and treasures (Ran 2013, pp. 23–24). The various reliquary objects found in the pagoda sites of Paekche’s Wanghŭng-sa and Mirŭk-sa, and Asukadera in Japan can be seen as the offerings that were given in the similar process of enshrining the śarīra. However, little is known about the excavated materials regarding the reliquary objects of the Chinese southern dynasties. If new materials are found in the future, we believe that detailed comparative studies can be conducted to identify the commonalities and differences among the reliquary objects of the southern dynasties of China, Paekche, and Japan.

4. Conclusions

With the excavations of Paekche’s Wanghŭng-sa and Mirŭk-sa, the Asuka Historical Museum in Japan is conducting the reorganization of artifacts that were unearthed from the heart stone of Asukadera’s wooden pagoda in 1957, but not yet classified properly. As scholars of various disciplines including archaeology, art history, architectural history, and conservation science are constructing an international cooperative system and analyzing the materials, Japan’s oldest śarīra enshrinement ritual is gradually revealing its nature.

The Asuka Historical Museum conducted a re-examination of various objects such as beads, pearls, horse gear, ceramics, earrings, gold and silver products, mica, and śarīra containers from the Kamakura period. This new analysis revealed that, excluding the śarīra containers, most of the items are likely artifacts from the Asuka period dating back to 593 when Asukadera was first constructed. Furthermore, similarities were found between the attire-related ornaments worn by nobles who participated in the ritual of placing pagoda deposits with the heart stone of the wooden pagoda at Asukadera, and the reliquary objects found at the Wanghŭng-sa and Mirŭk-sa sites in Paekche. However, differences in attire between Paekche and Japan were observed, particularly in the form and composition of metal artifacts such as crowns and belts. Horse gear and lamellar armor found only at Asukadera is similar to that from Japan’s Kofun period, indicating that while Japan adopted Buddhism from Paekche, it did not completely replicate it in the exact same form.

Members of the Japanese ruling class who participated in the ceremony of enshrining relics in the pagoda of Asukadera visually experienced differences with Paekche attire, and in the first half of the 7th century, a system was established for officials to wear clothes and ornaments according to their ranks. Through comparative studies of the reliquary objects unearthed from the pagoda site of Asukadera, this study is significant in its ability to elucidate, to some extent, the process of Japan’s adoption of Buddhism and the formation of its ancient state. Although the work of reorganizing and reclassifying the reliquary objects from Asukadera still has a long way to go, we look forward to sharing its entire result with scholars worldwide.