September 13, 1791 Tsunami: Oasaka Bay, Japan
A tsunami caused by a magnitude 6.5 earthquake began at Oasaka Bay, Japan on September 13, 1791. Its effects were recorded at 1 place.
Where the waves reached
The source (white) and every runup with a place, colored by the water height recorded there. A ring is a runup NCEI marks doubtful.
- Under 1 m
- 1 to 3 m
- 3 to 10 m
- 10 to 30 m
- 30 m and more
- Height not recorded
The tsunami
- Date
- September 13, 1791
- Source
- Oasaka Bay, Japan
- Cause
- Earthquake
- Earthquake
- Magnitude 6.5
- Runups recorded
- 1
- Tsunami intensity (Soloviev-Imamura)
- 1
- Tsunami magnitude (Iida)
- 1
- Waters
- Ocean
- How certain
- Probable tsunami
- Source location
- 34.500° N, 135.400° E
The toll
- Deaths
- Some (about 51 to 100)
- Damage
- Limited (under about $1 million)
Where the literature gives no number, NCEI records a description on a scale of 1 to 4, printed here in its words. Damage is in millions of US dollars of the year of the event, not adjusted for inflation.
What the record says
NCEI’s account, from the sources it cites.
Reference #150:
Sakai, Izumi tsunami. Stone wall construction of
fields destroyed, some deaths. Kyoto, Izumi Sakai
earthquake. (
Reference #414:
1791, September 13. An earthquake occurred with source in Osaka bay. A tsunami was observed at Sakai. This may have been a tsunami of storm origin, as thought by Imamura and Musya (Imamura, 1949; Musya, 1951).
Every runup
Nearest the source first. Heights are above sea level at the time; a tide gauge reads half the wave’s full height.
| Where | Country | Km from source | Water height, m | Inland, m | Measured by | First wave, UTC | Deaths |
|---|---|---|---|---|---|---|---|
| Sakai | Japan | 14 | Eyewitness observation of water height |
More
Every tsunami in 1791The 1700sTsunamis of JapanThe earthquakeThis day in weather historyAlerts in force
Sources
Tsunami events and runups from NOAA’s National Centers for Environmental Information, Global Historical Hazard Database, cited as NCEI/WDS, doi:10.7289/V5PN93H7. Public domain. Read 2026-09-24. NCEI tsunami event 558.