November 27, 850 Earthquake: Yomagata, Shonai, Japan
A magnitude 7 earthquake struck Yomagata, Shonai, Japan on November 27, 850. It caused a tsunami.
Map
Where it struck, with the other significant earthquakes within 200 km. Circles are sized and colored by magnitude; select one for its page.
The earthquake
- Date
- November 27, 850
- Place
- Yomagata, Shonai, Japan
- Magnitude
- 7 (Ms)
- Tsunami
- Yes: the tsunami it caused
- Epicenter
- 39.000° N, 139.900° E
- Country
- Japan
The toll
- Deaths
- Many (about 101 to 1,000) with its tsunami and other effects
- Damage
- Moderate (about $1 to $5 million) with its tsunami and other effects
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:
Nov 27, 850. 39 N. 139.9 E, magnitude 7. Landslide, ground cracked. Many deaths. Mogami river sides destroyed and inundated 4 km inland from Kofufu. Tsunami damage at Kisagata.
Reference #414:
Nov 27, 850, 39.1 N, 140 E, magnitude 7.9, event validity possible. There was a strong earthquake in the Shonai locality (Yamagata Prefecture). A tsunami was observed on the coast of the Sea of Japan. Its source was presumably located to the northwest of Sakata near the coast and south of the source of the earthquake of 1804.
Iida (1956): 39 N., 139.5 E.; M=7, m=1.
Iida et al. (1967): 39.1 N., 140 E.; M=7.9, m=1.
Other significant earthquakes nearby
Within 200 km, the deadliest first.
- September 27, 1611, Aidu, Japan
- December 18, 1828, Sandyo IN Etigo, Japan
- July 10, 1804, Kisakata, Japan
- June 19, 1694, Ugo, Japan
- August 31, 1896, Senhoku, Ugo, Japan
- October 18, 1644, NW. Honshu Island, Japan
- May 26, 1983, Akita, Honshu, Japan
- March 15, 1914, Senhoku, Japan
- December 7, 1833, NW, Honshu, Japan
- September 25, 1810, Oga, Japan
- April 21, 1659, Aidu, Japan
- June 16, 1964, W Coast, Honshu, Japan
- May 1, 1939, NW, Honshu, Japan
- June 13, 2008, Tokyo, Honshu, Japan
- April 7, 2011, Near E Coast Honshu, Japan
More
Significant earthquakes of 850The 800sRecent earthquakes near hereThis day in weather history
Sources
Significant earthquakes 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 earthquake 5899.