Tsuyama massacre

What Happened

On the night of 21 May 1938, a 21-year-old man named Mutsuo Toi (都井 睦雄, Toi Mutsuo) carried out a mass murder in the rural village of Kamocho Yukishige, near Kamo in Tsuyama, Okayama Prefecture, in the Empire of Japan. He killed 30 people, among them his own grandmother, and seriously injured three others. He then killed himself with a shotgun.

Toi was armed with a Remington shotgun, a katana (刀, かたな — a long curved Japanese sword), two daggers and an axe. The killings took place at night, moving through the village. The death toll of 30 makes it the deadliest shooting by a lone gunman in Japanese history.

The date fell in the 13th year of the Shōwa era (昭和, しょうわ), the reign period of Emperor Shōwa, better known outside Japan as Hirohito. The Shōwa period ran from 1926 to 1989.

Background

Mutsuo Toi lived in a small farming community where close neighbours knew one another's affairs in detail. In May 1937 he was diagnosed with tuberculosis, a disease then widely feared and heavily stigmatised in rural Japan. The diagnosis changed how the village treated him.

Before his illness, Toi had had premarital sexual affairs with young women in the village. After the diagnosis, those women rejected his advances. His suicide notes indicate that revenge for this social rejection and stigmatisation was his motive for the murders. The combination of a stigmatised illness, sexual rejection, and a tight-knit community in which everyone knew his history formed the background to the attack.

Why It Mattered

The scale of the killing — 30 dead by a single attacker — set a record in Japan that has not been surpassed. The case became known in Japanese as the Tsuyama incident, and it has been retold repeatedly in Japanese crime writing, film and television.

The murders also exposed how a rural community handled a stigmatised disease. Tuberculosis carried enormous social weight in early twentieth-century Japan, and the case became a reference point in later discussion of how illness, isolation and humiliation can combine. The fact that Toi killed his own grandmother, and then himself, left the village without any defendant to try — no courtroom, no verdict, only the written notes he left behind.

The Name in Japanese

The Japanese name of the event is 津山事件.

• Kana reading: つやまじけん
• Romaji: Tsuyama jiken

Note that the kana reading supplied for this entry, つやまさんじゅうにんごろし, is a descriptive phrase rather than the standard name of the incident. It translates roughly as "the Tsuyama thirty-person murder", and it is the kind of blunt label that circulated in popular retellings. The formal name used in writing is 津山事件.

Breaking 津山事件 down character by character:

津 — read here as つ (tsu). The character means a crossing point, a ford, or a harbour. It appears in place names across Japan and is the first element of Tsuyama.

山 — read here as やま (yama). It means mountain. Together, 津山 (Tsuyama) is the city in Okayama Prefecture where the killings took place.

事 — read here as じ (ji). It means matter, affair, or thing. It is the first half of the word for "incident".

件 — read here as けん (ken). It means matter, case, or item. Paired with 事, it forms 事件 (じけん, jiken), the standard Japanese word for an incident, case or affair — the term used for crimes, scandals and historical episodes alike.

So 津山事件 is literally "the Tsuyama affair": a place name followed by the ordinary word for a case. Japanese does not need a separate vocabulary for massacres to name one; 事件 does the work, and the place name supplies the rest. Readers will meet this pattern constantly — a location plus 事件 — in Japanese news and history writing.

The alternative label つやまさんじゅうにんごろし breaks down as 津山 (Tsuyama), 三十人 (さんじゅうにん, sanjūnin — thirty people), and 殺し (ごろし, goroshi — killing, from the verb 殺す, ころす, korosu, to kill). It is a plain description rather than a formal name.

Key Figures

Mutsuo Toi (都井 睦雄, Toi Mutsuo) — the perpetrator. He was 21 years old at the time of the killings. He had been diagnosed with tuberculosis in May 1937, roughly a year before the attack. He killed 30 people, including his grandmother, and seriously injured three others, then killed himself with a shotgun. His suicide notes set out revenge for social rejection and stigmatisation as his motive.

The victims — 30 people died, three more were seriously injured. The dead included Toi's grandmother. The village concerned was Kamocho Yukishige, near Kamo, in Tsuyama, Okayama Prefecture.

The young women of the village — before his diagnosis, Toi had had premarital affairs with young women in the village. After the diagnosis, they rejected his advances. This rejection is recorded in his suicide notes as the grievance behind the killings.