Significant earthquakes of 1820

1820 Earthquake: Loango, Congo

1820 · M6.2 · Deaths: many

A magnitude 6.2 earthquake struck Loango, Congo in 1820. 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
1820
Place
Loango, Congo
Magnitude
6.2 (Mfa)
Intensity
5 on the Modified Mercalli scale
Epicenter
4.500° S, 11.600° E
Country
Congo

The toll

Deaths
Many (about 101 to 1,000) with its tsunami and other effects
Damage
Limited (under about $1 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.

1820. The earliest reported seismic sea-wave was associated with an earthquake about 1820 in Loango on the coast of Congo. ...the earthquake, or seaquake, that occurred at Cabenda... This is quite clearly the description of a relatively large seismic sea-wave associated with an earthquake which was felt over a very large area of West Africa. (reference #1214)

More

Significant earthquakes of 1820The 1800sRecent earthquakes near here

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 7978.