The Honjo Masamune Disappearance

On August 15, 1945 (Shōwa 20), Japan accepted the Potsdam Declaration and surrendered unconditionally. Under the occupation administration of the GHQ (General Headquarters of the Supreme Commander for the Allied Powers), a 'Weapons Surrender Order' was issued nationwide, and the confiscation of weapons, including swords, began. Amid the confusion of this occupation period, the Honjō Masamune, regarded as one of the finest blades in the history of the Japanese sword, was lost forever. Its loss is not merely the disappearance of a cultural property. It marks the end of the spiritual meaning that the Japanese sword had held as 'the soul of the samurai,' and it still leaves a deep wound in the hearts of sword enthusiasts, historians, and those involved in cultural property protection.

What Was the Honjō Masamune? — The Pinnacle of the Late Kamakura Period

Masamune is regarded as one of the greatest swordsmiths in the history of the Japanese sword. He was active in Kamakura, in Sagami Province (present-day Kanagawa Prefecture), during the late Kamakura period (late 13th to early 14th century). As the perfecter of the Sōshū tradition, his works became the standard for all swordsmiths of later generations, owing to the beauty of the internal iron structure called jikei and to his superb forging technique, which achieved both flexibility and hardness. It is also said that Masamune's disciples and successors (the Masamune Jittetsu, or Ten Disciples of Masamune) scattered across various regions and nurtured the various schools of Japanese swordsmithing.

The Honjō Masamune is one of the most renowned blades among Masamune's works. It took its name from its possession by Honjō Shigenaga, a warlord of Echigo (present-day Niigata Prefecture), during the Sengoku period.

The Provenance of the Honjō Masamune — From the Sengoku Period to the Tokugawa

The provenance of the Honjō Masamune runs through the core of the warrior society from the Sengoku period to the Edo period. It is said that Honjō Shigenaga obtained the blade on the battlefield, and that, in hardship, he passed it to Toyotomi Hidetsugu. It then passed through the hands of Toyotomi Hideyoshi and Shimazu Yoshihiro, among others, and came into the collection of Tokugawa Ieyasu.

After the Edo period began, the Honjō Masamune was strictly managed by the Tokugawa shogunal family as an 'otemoto odōgu' (articles kept at hand). It is also recorded in the Kyōhō Meibutsu-chō (Register of Famous Swords of the Kyōhō Era), a catalogue of famous swords compiled at the order of Tokugawa Yoshimune, the eighth shogun. This makes clear that the Tokugawa family preserved it as the finest sword under heaven. After the Meiji Restoration it was passed down to the Tokugawa main house, and even in modern times it was kept hidden as a 'treasure of the Tokugawa family.'

The Seizure by the GHQ — The Sword Confiscation Order Under the Occupation

Immediately after the defeat of 1945 (Shōwa 20), as part of the dismantling of Japan's armaments and its disarmament, the GHQ ordered the seizure of privately held swords and weapons. The order initially targeted mainly military weapons, but in practice, swords held by ordinary citizens, samurai families, and sword collectors were also widely confiscated.

Following the GHQ's weapons seizure order, Japanese swords were brought to police stations and the offices of the Military Government across the country. It is estimated that during this period at least tens of thousands of Japanese swords (some accounts say hundreds of thousands) were confiscated, destroyed, or taken overseas. This large-scale seizure was extremely poorly managed, because the cultural value of Japanese swords was insufficiently recognized even within the GHQ, and because on-site U.S. soldiers often privately took swords away as souvenirs.

Tokugawa Iemasa, head of the Tokugawa main house, submitted fourteen family-treasured famous swords, including the Honjō Masamune, to the Mejiro Police Station in December 1945, in accordance with the GHQ's order. The Tokugawa family's famous swords, including the Honjō Masamune, became subject to seizure at this time.

Records of the Seizure — Sergeant Coldy Bimore

The most specific record currently known regarding the seizure of the Honjō Masamune is a record from January 1946, when the Mejiro Police Station handed the swords over to the U.S. military. According to this record, the person who received the swords, including the Honjō Masamune, was a U.S. Army sergeant recorded as Coldy Bimore (Sgt. Coldy Bimore), said to belong to the Foreign Liquidations Commission of the Army Forces Western Pacific (AFWESPAC).

However, this record itself may have transcribed the name from a distorted pronunciation. Neither the identity of the person 'Bimore' nor the present-day descendants have been identified. The whereabouts of the Honjō Masamune remain unknown to this day.

The Meaning of the Japanese Sword's 'Soul' — The Cultural Impact of the Loss

The loss of the Honjō Masamune holds special meaning because it means the loss of the core of the spiritual and cultural significance of the Japanese sword, not merely the disappearance of a cultural property.

Masamune is widely recognized, not only among sword enthusiasts and researchers but also among the general Japanese public, as the 'greatest swordsmith in the history of the Japanese sword.' Several of Masamune's swords are currently designated as National Treasures or Important Cultural Properties and are displayed at the Tokyo National Museum, the Kyoto National Museum, and other venues. However, the Honjō Masamune occupied a special place in sword history among them, as a single blade that represented the pinnacle of Masamune's swordsmithing skill.

The fact that 'the soul of the Japanese sword was lost forever in the aftermath of the war' gave a profound shock to those who have cherished the Japanese sword as 'the soul of the samurai and a symbol of Japanese culture.' The inadequate protection of cultural properties under occupation rule was shown most vividly by the loss of the Honjō Masamune.

The Search Since — A Mystery Still Unfolding

The search for the Honjō Masamune has continued intermittently from the postwar period to the present. Sword-related people in Japan and abroad have called for information, but no decisive lead has been obtained.

Since the twenty-first century, searches have continued in various forms, including calls for information on the internet and attention to antique markets and auction listings in the United States. However, as of 2026, the whereabouts of the Honjō Masamune remain unknown.

The loss of the Honjō Masamune is the most symbolic incident showing how the Japanese sword was buffeted by the upheavals of history. The blade that a Sengoku warlord protected at the risk of his life, that the Tokugawa shogunal family kept hidden for three hundred years, and that became the standard for all later swordsmiths with its sharpness and beauty, disappeared in the chaos of defeat. Its loss means that the role of the Japanese sword as 'a bridge to a past age' has been permanently severed, and it leaves an enduring scar in the hearts of everyone who loves swords. The quest for the Masamune blade is also a journey that keeps asking what the Japanese sword itself means.