Armor buried under Japanese temple linked to ancient Korean kingdom
Few cultures exist in a vacuum, even those separated from others by hundreds of miles of sea, like the island nation of Japan. Nearly 70 years ago, archaeologists discovered ancient armor beneath one of the island nation’s most important historical sites. Now, researchers can finally trace the telltale craftsmanship of this 1,400-year-old armor in Korea. Specifically, to the Baejke Kingdom, one of the three major Korean empires dating back to the 18th century BCE.
Buddhism really began to flourish in Japan from the 6th century CE, after the arrival of monks from mainland China and Korea. Few places represent this monumental cultural shift more than the Asuka-dera temple complex, located about 23 miles southeast of Osaka.
The establishment of Asuka-Dera in the early 7th century marked the first large-scale Buddhist temple in the island archipelago.
According to ancient documents, including the second oldest history of Japan, Nihon Shokiartisans and monks from the Baekje Kingdom helped build the temple complex. Baekje was one of the “Three Kingdoms of Korea” that flourished between the 18th century BCE and 660 CE.
Archaeologists from the National Research Institute of Cultural Properties in Nara initially located the armor fragments beneath the foundations of a pagoda during excavation work conducted in 1957. Although its construction resembled armor previously linked to the royal sites of Baekje in Korea, technology at the time was not advanced enough to provide a definitive answer.
However, in 2015, equipment such as X-rays and 3D imaging finally allowed researchers to examine the Asuka-dera armor in more detail. They discovered that, like Baekje’s armor, the Japanese monastery finds were made by interweaving small iron plates with ropes in what is called a lamellar structure. This approach offered wearers solid protection without sacrificing flexibility, particularly because the torso, upper arm, and shoulder segments were all connected into a single piece of shirt-like armor.
Similar armor discovered between 2011 and 2014 in Gongsanseong Fortress, a historic complex in Baekje located about 80 km southeast of Seoul, also supports this hypothesis. In the fortress, researchers identified plaque inscriptions dating to 645 CE, around the same time as Asuka-Dera was built. In 2024, archaeologist Takehiro Hasumura confirmed the overlaps after personally examining the Gongsanseong specimens.
In the 7th century, elite Japanese warriors began to adopt keiko-style armor. Like the Baejke model, keiko armor is made of intertwined and flexible lamellar iron scales. The adoption of the Keiko, as well as its design, now shows more clearly than ever that Baekje craftsmen, particularly armorers, traveled alongside Buddhist monks and emissaries from the mainland.
With additional excavation projects, archaeologists hope to further contextualize other crucial cultural exchanges between these and other East Asian kingdoms.
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