The Mystery of Masakado’s Mound: Tokyo’s Most Sacred Curse
In the heart of Tokyo’s Otemachi district, surrounded by gleaming skyscrapers and the hustle of Japan’s financial elite, lies a small, stone-walled enclosure that time—and fear—has refused to erase. This is the Masakado no Kubizuka, or the Head Tomb of Taira no Masakado. To the unobservant tourist, it may look like a mere historical marker. However, to locals and history buffs, it is ground zero for one of Japan’s most enduring and terrifying urban legends.
While Tokyo is a city that relentlessly modernizes, this specific plot of land remains untouched, protected by a centuries-old fear of a samurai’s vengeful spirit. Visiting the tomb offers a fascinating glimpse into the spiritual undercurrents that still flow beneath the concrete of modern Japan.
Origins: The First Samurai Rebel
To understand the gravity of the site, one must look back to the Heian Period. Taira no Masakado (?–940 AD) was a powerful landowner and samurai in the Kanto region. He is a figure of immense historical significance, often cited as the first samurai to lead a major rebellion against the central imperial government in Kyoto.
Frustrated by local politics and the distant, ineffective rule of the Emperor, Masakado expanded his territory by force. In a bold act of defiance, he declared himself the “New Emperor” (Shinno). This was an unprecedented act of treason. The central government in Kyoto quickly dispatched forces to quell the uprising. In 940 AD, during the Battle of Kojima, Masakado was killed. His rebellion was short-lived, but his legacy was just beginning.
The Legend of the Flying Head
According to historical records and folklore, after Masakado was killed, his head was severed and taken to Kyoto to be displayed on a spike as a warning to other potential rebels. This was standard practice at the time, but Masakado was no standard warrior.
Legend has it that the head did not decompose. Instead, for three months, it gnashed its teeth and shouted insults at onlookers. One night, fueled by rage and a longing for his body back in the Kanto region, the head lifted into the air and flew eastward. It is said to have eventually exhausted its energy and fell to the ground in a village called Shibasaki—which is now part of the Otemachi district in Tokyo.
Villagers, terrified of the angry spirit, washed the head and buried it respectfully, erecting a mound to appease the onryo (vengeful spirit). This mound is what remains today as the Kubizuka.
Modern Culture: The Curse That Stopped Construction
The reason Masakado’s Head Tomb remains in one of the world’s most expensive real estate districts is not just due to historical preservation, but genuine superstition known as the “Masakado Curse.”
The Ministry of Finance Incident (1923)
Following the Great Kanto Earthquake of 1923, the Ministry of Finance attempted to clear the rubble and the tomb to build a temporary office building. Within a short period, the Minister of Finance and roughly a dozen other officials involved in the project died suddenly or suffered severe accidents. Attributing this to Masakado’s anger, the building was demolished, and the mound was restored.
The US Occupation Incident (1945)
After World War II, American occupation forces tried to level the land to build a parking lot. As the story goes, a bulldozer attempted to clear the tomb but flipped over mysteriously, killing the driver. Local officials pleaded with the US military to leave the site alone, explaining the history of the curse. The plans were subsequently abandoned.
Corporate Respect
Today, the site is maintained by a preservation group formed by nearby corporations, including the Mitsubishi UFJ Financial Group. It is a well-known unspoken rule in Otemachi that office desks should never be positioned so that employees have their backs to the tomb, as it is considered a sign of disrespect that invites bad luck.
Traveler’s Tips: Visiting the Tomb
If you wish to pay your respects to Japan’s rebellious samurai, here is what you need to know:
- Location: The tomb is located just outside the C5 exit of Otemachi Station (Marunouchi, Tozai, Chiyoda, Hanzomon, and Mita subway lines). It is wedged between high-rise office towers.
- Etiquette: This is a spiritual site, not a typical tourist attraction. It is appropriate to bow slightly before entering the enclosure. You will see locals clasping their hands in prayer. Please maintain silence and do not take disrespectful selfies.
- The Frogs: You will notice many stone statues of frogs around the tomb. In Japanese, “frog” is kaeru, which is a homophone for “to return.” Originally, this symbolized the head’s desire to return home. Today, people pray here for the safe return of loved ones or kidnapped victims.
Sources & Further Reading
For those interested in the deep history of Japanese mythology and the lineage against which Masakado rebelled, the classic texts are essential reading:
- Shomonki (The Chronicle of Masakado): A mid-Heian period war chronicle (gunki monogatari) that details the life and rebellion of Taira no Masakado. It is the primary historical source for his uprising.
- Nihon Shoki (The Chronicles of Japan): While written centuries before Masakado, this text establishes the divine lineage of the Imperial family, providing the context for why Masakado’s claim of being a “New Emperor” was such a blasphemous and significant historical event.
Visiting the Masakado no Kubizuka is a quick but powerful reminder that in Tokyo, the past is never truly dead—it is just waiting beneath the surface.