1925 North Tajima earthquake

What Happened

On 23 May 1925, an earthquake struck the northern part of Hyōgo Prefecture (兵庫県, Hyōgo-ken) on the Sea of Japan coast of central Honshu. The town at the centre of the damage was Toyooka (豊岡, Toyooka), a castle town in a narrow river basin surrounded by mountains. The shock is recorded at coordinates 35.5633° N, 134.8333° E, placing the epicentre in the Tajima region of northern Hyōgo.

The earthquake takes its English name, North Tajima, from the old provincial name for that district. In Japanese it is called the Kitatajima jishin (北但馬地震), literally the "North Tajima earthquake".

Background

The earthquake occurred in the 14th year of the Taishō era (大正, Taishō), the reign of Emperor Taishō, which ran from 1912 to 1926. The Taishō period was a short one by Japanese imperial standards, and it was also an era of rapid urbanisation: railways, gas lighting, telephone lines and modern brick and timber construction were spreading through regional towns like Toyooka.

Tajima Province (但馬国, Tajima-no-kuni) was an old administrative division of pre-modern Japan, covering the northern, Sea of Japan side of what is now Hyōgo Prefecture. When the province system was abolished in the early Meiji period and replaced by prefectures, the Tajima districts were folded into Hyōgo Prefecture, whose capital, Kōbe, lies far to the south on the Pacific side. Northern Hyōgo remained a distinct region, separated from the rest of the prefecture by the Chūgoku mountain range, and it retained the name Tajima in local usage.

Northern Hyōgo sits near the boundary of the Eurasian and Philippine Sea tectonic plates, and the region has a long record of seismic activity. The 1925 event was one of several destructive earthquakes to strike the Kinki and Hokuriku regions in the early twentieth century.

Why It Mattered

The 1925 North Tajima earthquake struck Toyooka and the surrounding Tajima districts, damaging the town and the rural settlements of the river basin. Coming three years before the far larger Great Kantō earthquake of 1923 — no, in fact three years after it — the North Tajima quake belongs to a cluster of disasters that pushed Japanese authorities to rethink how the country built and rebuilt its towns.

The Great Kantō earthquake of 1 September 1923 had levelled much of Tokyo and Yokohama and killed tens of thousands. The 1925 North Tajima earthquake, smaller in scale but still locally devastating, reinforced the sense that Japan's building stock and emergency response were inadequate. In the years that followed, Japanese engineers and planners increasingly turned to seismic-resistant construction and to formalised urban rebuilding programs, a shift that would shape Japanese cities for the rest of the century.

For Toyooka itself, the earthquake became a marker in the town's modern history, remembered alongside the great fires and floods that periodically swept the Tajima basin. The event also left its mark on the region's identity: the name "North Tajima" tied the disaster to a place that had already lost its status as a province and was now known mainly through its prefectural designation.

The Name in Japanese

The Japanese name of the earthquake is 北但馬地震.

• Kana reading: きたたじまじしん
• Romaji: Kitatajima jishin

Broken down character by character:

• 北 — read here as きた (kita). Meaning: "north". It specifies that the earthquake struck the northern part of Tajima, distinguishing it from other events in the same old province.
• 但 — read here as た (ta), the first element of Tajima. Meaning: in this word, the character is used purely for its sound and as the first kanji of the old provincial name 但馬. On its own the character has the sense of "only" or "provided that", but that meaning plays no role here.
• 馬 — read here as じま (jima), the second element of Tajima. Meaning: "horse". The combination 但馬 is an old place name whose kanji were fixed by convention; the literal meanings of the two characters do not describe the region.
• 地 — read here as じ (ji). Meaning: "earth" or "ground". It is the first element of the compound for earthquake.
• 震 — read here as しん (shin). Meaning: "shake" or "tremor". Together, 地震 (jishin) means "earthquake".

So the full name parses as "north + Tajima + earthquake": the earthquake of northern Tajima. The reading きたたじまじしん follows the standard Japanese pattern for place-name plus 地震, with the place name read in its native Japanese (kun'yomi) pronunciation and 地震 read in its Sino-Japanese (on'yomi) pronunciation.

Key Figures

The earthquake struck Toyooka (豊岡, Toyooka), the principal town of the Tajima region and the seat of local government for northern Hyōgo Prefecture. The event is dated to 23 May 1925, in the 14th year of the Taishō era, during the reign of Emperor Taishō. Its epicentre is recorded at 35.5633° N, 134.8333° E, in the Tajima district of Hyōgo Prefecture. The earthquake is named after Tajima Province (但馬国, Tajima-no-kuni), the pre-modern administrative division that covered the same area.