The 8.8–9.4 Caldera earthquake shakes Chile's Atacama Region causing tsunami in Chile, Hawaii, and Japan.

The 1420 Caldera earthquake was a pre-Columbian earthquake that shook the southern portion of Atacama Desert in the early morning of 31 August 1420 and caused tsunamis in Chile as well as Hawaii and the towns of Japan. The earthquake is thought to have had a size of 8.8–9.4 M_w. Historical records of the tsunami exist for the Japanese harbours of Kawarago and Aiga where confused residents saw the water recede in the morning of 1 September, without any sign of an earthquake. In Chile, rockfalls occurred along the coast as well, producing blocks of up to 40 tons that are now found inland. This is also consistent with the identification of a possible tsunami deposit in Mejillones Bay that has been dated to the range 1409 to 1449. Deposits found by coring of recent sediments in a wetland near Tongoy Bay have also been linked to the 1420 tsunami.

The Atacama Region is one of Chile's 16 first order administrative divisions. It comprises three provinces: Chañaral, Copiapó and Huasco. It is bordered to the north by Antofagasta, to the south by Coquimbo, to the east by the provinces of Catamarca, La Rioja and San Juan of Argentina, and to the west by the Pacific Ocean. The regional capital Copiapó is located 806 km (501 mi) north of the country's capital of Santiago. The region occupies the southern portion of the Atacama Desert, the rest of the desert is mainly distributed among the other regions of Norte Grande. As a generalization south of Copiapó River the region is mostly semi-arid and north of it is a true desert. The inland area in the north also differs from the southern part by hosting active volcanoes part of the Central Volcanic Zone of Andes. The region has a long tradition of mining.

A tsunami is a series of waves in a water body caused by the displacement of a large volume of water, generally in an ocean or a large lake. Earthquakes, volcanic eruptions and underwater explosions above or below water all have the potential to generate a tsunami. Unlike normal ocean waves, which are generated by wind, or tides, which are in turn generated by the gravitational pull of the Moon and the Sun, a tsunami is generated by the displacement of water from a large event.