* Image is for illustrative purposes only.Yayoi and Kofun Periods
弥生・古墳時代
The primordial stage before the emergence of the Japanese sword. Iron straight swords transmitted from the continent—China and the Korean Peninsula—became established in the Japanese islands, accumulating metallurgical techniques and laying the foundation for sword culture. Iron swords and blades interred in ancient burial mounds (kofun) serve as precious witnesses to this era's sword history.
Description
Arrival and Establishment of Iron Implements
In the Yayoi period, iron products from the continent began to flow into the Japanese archipelago via the Korean Peninsula. The earliest iron implements were mainly agricultural and carpentry tools rather than weapons. From the middle to late Yayoi period, iron swords and similar items began to be excavated as grave goods, and in the 1st century CE, continental iron chokutō (tachi, ancient straight sword) also began to flow in. These iron implements were initially imported goods, and they are thought to have been made in workshops in the southern part of the Korean Peninsula (the Gaya and Samhan regions). Domestic extraction and smelting of satetsu (iron sand) and iron ore, the raw materials for iron, had not yet become full-scale in this period.
Establishment of Iron-Smelting Technology in the Kofun Period
In the Kofun period (late 3rd to 7th century), immigrant artisans (toraijin) from the Korean Peninsula, particularly technician groups of Baekje and Gaya lineage, brought full-scale iron-smelting technology to the Japanese archipelago. Furnaces that formed the prototype of tatara iron smelting were established in the Chūgoku region (around present-day Shimane, Tottori, and Okayama) and in the Kinki region, and the technique of directly reducing iron from satetsu began to take root. The satetsu of Izumo was of high quality, and it laid the foundation for an excellent iron-producing region later known for "Izumo satetsu."
Types and Characteristics of Grave-Good Swords
Iron swords buried with tumuli are classified into various types, including kantō tachi (ring-pommel sword), single-phoenix ring-pommel sword, twin-dragon ring-pommel sword, and keitō tachi. These tachi were strongly influenced by Han and Six Dynasties culture in China, and many have ring-shaped ornaments on the pommel (tsukagashira). The blade is basically a straight chokutō without curvature. The quality of the iron was still uneven, and the elaborate layered forging (sekisō tanren) seen in later Japanese swords has not been confirmed. However, some outstanding examples show traces of heat treatment, yaki-ire (quenching).
Political Significance of Swords Buried in Tumuli
Swords buried with tumuli were not mere weapons but prestige goods symbolizing the authority and status of the deceased. The Yamato kingship (Yamato seiken) formed and strengthened its network of control by bestowing iron swords on influential regional chieftains. The Seven-Branched Sword (Shichishitō), an iron seven-pronged sword currently transmitted at Isonokami Jingū, is famous as a diplomatic gift presented by Baekje to the king of Wa, and it clearly illustrates the diplomatic relations with the continent in this period and the political function of swords. The silver-inlaid inscribed tachi excavated from the Eta Funayama Tumulus in Kumamoto Prefecture (bearing the inscription "…Great King who rules the realm…") is also an important relic of this period.
Position as the Prehistory of the Nihontō
The chokutō of the Yayoi and Kofun periods still lack the three elements that characterize the Nihontō: curved blades, layered forging with a composite structure of kawagane and shingane, and hamon formation through quenching. However, the iron-smelting technology, sword-processing technology, and cultural and political position of swords accumulated in this period became the foundation for the birth of the Nihontō after the Heian period. It was also during this long prehistoric era that the refinement of the smelting technology for wa-tetsu, the precursor of tamahagane, and the cultivation of a culture that invested swords with spirituality and symbolism took place. For collectors, relics of this period are positioned as the archaeological origin for understanding the deep roots of Nihontō culture.
Characteristics of This Era
- All blades are straight swords (chokutō) with no curvature. They were directly influenced by the straight-sword culture of the continental mainland and the Korean Peninsula, and the 'curvature' that characterizes later Japanese swords did not yet exist
- The representative type is the kantō tachi (ring-pommel sword), with a ring ornament on the pommel (tsukagashira). Designs are varied, including single-phoenix, twin-dragon, and three-leaf motifs, reflecting the aesthetic sense of Han and Six Dynasties culture
- Iron production was carried out mainly by immigrant artisans (toraijin), and the prototype of tatara iron smelting took shape in the Chūgoku region and Kinki. This was an important era in which wa-tetsu began to be produced through the reduction of iron sand
- Buried swords were prestige goods indicating the political status and authority of the deceased. A control network was formed through a system in which the Yamato kingship bestowed swords on regional chieftains
- Laminated forging (a composite structure of kawagane and shingane) is not yet seen in the blades, and iron quality is uneven. However, some fine examples show traces of heat treatment (yakiire)
- This was an era in which swords functioned as diplomatic gifts exchanged with the continent. The Seven-Branched Sword (Shichishitō) of Isonokami Jingū, a gift from Baekje to the king of Wa, is a typical example