NARA - Japan’s oldest coin is often said to be Wado Kaichin, a name many people remember from school textbooks, but an even older form of coinage was discovered in Asuka Village in 1999, triggering widespread attention and forcing historians to rethink the origins of Japanese currency.
The discovery was made at the Asuka Ike Workshop ruins in Nara Prefecture, a site that revealed clear evidence of Japan’s earliest coin-minting activity, along with a series of other groundbreaking finds, including the oldest known wooden tablets inscribed with terms still used today, making the site one of the most significant archaeological discoveries linked to the foundations of Japanese manufacturing.
The investigation team visited Asuka Village, often described as the birthplace of Japan, home to numerous “firsts” in Japanese history, including Asukadera, the country’s first full-scale Buddhist temple, and the Mizuo-chi ruins, where Japan’s earliest timekeeping device is believed to have been created.
The focus of the investigation was the origins of money, at a location where imperial palaces were built during four different phases of the Asuka period, including the remains of a well associated with Kiyomihara Palace from the reign of Emperor Tenmu, whose era became central to the discoveries made nearby.
For decades, Japan’s first currency was believed to be Wado Kaichin, minted around August 708, but in 1999, archaeologists confirmed the existence of an even older coin type known as Fuhonsen at the Asuka Ike Workshop site, located only a short distance away, establishing it as the oldest coin known to have been produced in Japan.
The workshop ruins themselves were first identified in 1991, and subsequent excavations uncovered fragments of unfinished Fuhonsen coins, typically found in pairs, providing clear proof that the coins were being manufactured on site rather than imported or produced solely for ritual purposes.
Archaeologists also discovered gold, silver, glass products and earthenware, indicating that the site functioned as a large-scale, integrated production facility, unlike anything previously known from the period.
Roughly 8,000 wooden tablets were excavated from the site, accounting for more than half of all such tablets found in the wider Asuka area, and among them was the oldest known example of the characters used to write “tenno,” offering vital clues about when the imperial title came into use.
The Asuka Ike Workshop ruins are located within the grounds of the Manyo Culture Museum, which recreates scenes from the Manyoshu, Japan’s oldest anthology of poetry, using models and visual displays to convey the lives and landscapes of the era, and visitors entering the museum are immediately confronted with the preserved remains of the workshop itself.
The site contains the remains of around 300 furnaces spread across an area of roughly 20,000 square meters, equivalent to about half the size of Koshien Stadium, and archaeological evidence shows that metals such as gold, copper and iron, along with glass, were melted, shaped and processed there, demonstrating an unprecedented level of industrial activity for the time.
Following the discovery, the ruins were carefully reburied for preservation, and the layout revealed through excavation was reconstructed above ground to reflect the site as it appeared during the Asuka period, after it was confirmed that the workshop lay beneath what had once been an Edo-period irrigation pond.
Further investigation into the coin production area revealed more than 500 fragments of failed or broken Fuhonsen coins, indicating large-scale manufacturing and distribution, since completed coins would have been shipped out, leaving only defective pieces behind.
While Wado Kaichin is confirmed to have circulated widely as official currency, historians continue to debate whether Fuhonsen functioned as circulating money or served a more limited role, although documentary records from the reign of Emperor Tenmu align closely with the evidence uncovered at the site, strengthening the case that Fuhonsen represented Japan’s earliest attempt at coinage.
In addition to coins, the site yielded evidence of advanced glassmaking and gold refining, including high-purity gold fragments, suggesting sophisticated production techniques that may have been introduced by craftsmen from the Korean Peninsula, where similar furnaces and materials have been found.
The workshop’s location, just 600 meters from the political center of the ancient capital, underscores its role as a state-run facility designed to centralize production, control materials and support the formation of an early centralized government.
The wooden tablets discovered at the site served a wide range of purposes, including production orders, delivery instructions, inventory tags, administrative records and fragments of religious texts, offering rare, direct insight into the administrative and economic systems of the time.
Among them, the tablet bearing the characters for “tenno” is considered the oldest surviving example of the term, although scholars continue to debate whether it referred explicitly to the emperor as a political title or carried a more religious or cosmological meaning, and even its precise reading remains a subject of discussion.
Due to their exceptional historical value, many of the artifacts uncovered at the Asuka Ike Workshop ruins have been designated as Important Cultural Properties, and museum displays now reconstruct scenes of coin casting, glass production and toolmaking to convey the scale and complexity of operations that once took place there.
The site is now regarded as the starting point of Japan’s integrated manufacturing tradition, offering a rare glimpse into how the technologies and systems that underpin modern Japanese industry first took shape more than 1,300 years ago.
Source: YOMIURI
