The New Madrid Earthquake, the largest earthquake ever recorded in the contiguous United States, occurred on February 7, 1812. (The largest recorded earthquake in the entire United States was the Alaskan Good Friday Earthquake on March 27, 1964.) It got its name from its primary location in the New Madrid Seismic Zone, near New Madrid, Louisiana Territory (now Missouri).

This earthquake was preceded by three other major quakes: two on December 16, 1811, and one on January 23, 1812. These earthquakes destroyed approximately half the town of New Madrid. There were also numerous aftershocks in the area for the rest of that winter.

There are estimates that the earthquakes were felt strongly over , and moderately across nearly one million square miles. The historic San Francisco earthquake of 1906, by comparison, was felt moderately over .