Kantotachi: Ring-Pommel Swords of the Kofun Period and Their Continental Origins and Japanese Transformation

What is the Kantou Tachi

"Kantou tachi (環頭大刀)" is a collective term for straight swords with ring-shaped metal decorations on the hilt pommel. The "kan" (環) refers to a circular ring, and "tou/gashira" (頭) refers to the decorative portion at the end of the hilt, with the name deriving from this characteristic pommel shape. These were primarily used and buried as grave goods in the Japanese archipelago during the Kofun period (late 3rd century to around 7th century) and maintain close connections with sword-making cultures of China and the Korean Peninsula.

Origins—Direct Importation of Continental Culture

The prototype of the kantou tachi is found in China. During the Han Dynasty through the Northern and Southern Dynasties period (220–589 CE) in China, straight swords with ring-shaped, dragon-shaped, and phoenix-shaped decorations on the hilt were used as prestige items by those in power. This culture is said to have been transmitted to the Japanese archipelago via the Korean Peninsula around the 4th to 5th centuries.

In the early period of transmission to Japan, it is believed that the products themselves were imported from the continent. However, from the late 5th through 6th centuries, kantou tachi began to be produced within the Japanese archipelago as well. Domestically produced kantou tachi, while building on prototypes from the continent and Korean Peninsula, underwent unique transformations that reflected Japanese metalworking techniques (such as plain rings, three-leaf, three-bead, and dragon-motif designs).

Pommel Shape and Classification

Kantou tachi are classified into multiple types based on the shape of the pommel.

Soken-tou: The simplest type with only a circular ring. These are thought to emphasize practicality over ornamentation. Many examples are found as grave goods.

Sanyou-kantou: A type with three-leaf-shaped decorations incorporated inside the ring. Influenced by continental three-leaf metalwork designs, these became widely popular in Japan as well.

Sanrui-kantou: A type with three bead-shaped decorations inside the ring. The character "rui" (累) refers to beads stacked upon one another and requires more complex metalworking techniques.

Ryumon-kantou: A type with dragon motifs applied inside or across the entire pommel. Considered the most formal style, these are often found as burial goods of high-ranking individuals. A prime example is the object unearthed from the Etafunayama Kofun in Kumamoto Prefecture.

Characteristics of the Blade

The blade of the kantou tachi is fundamentally a "chokutou" (straight sword)—a blade without curve and linearly straight. The edge may be single-edged or double-edged, and the cross-section of the blade exhibits shapes similar to shinogi-zukuri or hira-zukuri construction.

Blade lengths vary widely, ranging from the 30cm range for shorter examples to over 80cm for longer ones. The latter are called "tachi" and are thought to have been designed for use on horseback or in foot combat. The shape of the junction between the hilt and blade (the tang or nakago) also differs from later Japanese swords.

Development of Metalworking Techniques in Japan

Through the production of kantou tachi, metalworking techniques in the Japanese archipelago advanced dramatically. Inlay techniques using gold, silver, and copper, as well as casting and engraving techniques for gilt bronze, developed substantially during this period. The foundation of sword-mounting culture from the Nara period onward—fine metalwork such as tsuba, menuki, and fuchigashira—can be attributed to the accumulation of techniques cultivated during Kofun-period kantou tachi production.

From Kantou Tachi to Japanese Swords

From the late 7th through 8th centuries (the Nara period), a transition from direct importation of continental culture to distinctly Japanese culture progressed across various fields. In sword-making as well, a transition from straight-sword culture to curved-blade swords began. This transition did not occur overnight but resulted from the convergence of changes in cavalry combat tactics and the maturation of materials and forging techniques over the 9th and 10th centuries.

While kantou tachi cannot be called the "direct ancestors" of Japanese swords, they formed an important "foundation" for Japanese sword culture in the sense that they received continental culture and nurtured distinctive metalworking and forging cultures within the archipelago. While most extant kantou tachi are preserved in museums and shrine treasure halls, and very few can be directly owned by contemporary Japanese sword collectors, understanding them as the origin of sword history is essential for a fundamental grasp of Japanese swords.