<P> An undersea earthquake of estimated magnitude 7.4 occurred near Yaeyama Islands in the former Ryūkyū Kingdom (present day Okinawa, Japan) on 4 April 1771 at about 8 A.M. The earthquake is not believed to have directly resulted in any deaths, but a resulting tsunami killed an estimated 12,000 people (9,313 on the Yaeyama Islands and 2,548 on Miyako Islands). Estimates of the highest run - up on Ishigaki Island range from 30 to 85.4 meters (99 to 280 feet). The tsunami put an abrupt stop to population growth on the islands, and was followed by malaria epidemics and crop failures which further decreased the population . It took 148 years for the population to return to pre-tsunami levels . </P> <Tr> <Td> 1781 </Td> <Td> Pingtung, Taiwan </Td> <Td> </Td> <Td> </Td> <Td> In April or May 1781, according to Records of Taiwan County, in Jiadong, Pingtung County, a ten - foot wave engulfed the town . Fish and shrimp thrashed wildly on the shore and nearby fishing villages wiped out . However, there was no earthquake reported . A different source claims a 30 - meter (99 - foot) wave with also struck Tainan . A possibility is a misrecording of date, corresponding with the above Great Yaeyama event . </Td> </Tr> <Tr> <Td> 1783 </Td> <Td> Calabria, Italy </Td> <Td> 1783 Calabrian earthquakes </Td> <Td> Earthquake </Td> <Td> The earthquake was the second of a sequence of five shocks that struck Calabria . The citizens of Scilla spent the night following the first earthquake on the beach, where they were swept away by the tsunami, causing 1,500 deaths . The tsunami was caused by the collapse of Monte Paci into the sea, near the town . </Td> </Tr> <Tr> <Td> 1792 </Td> <Td> Kyūshū, Japan </Td> <Td> 1792 Unzen earthquake and tsunami </Td> <Td> Volcanic processes </Td> <Td> Tsunamis were the main cause of death for Japan's worst - ever volcanic disaster, an eruption of Mount Unzen, Hizen Province (Nagasaki Prefecture), Kyushu, Japan . Towards the end of 1791 a series of earthquakes on the western flank of Mount Unzen gradually moved towards Fugen - dake, one of Mount Unzen's peaks . In February 1792, Fugen - dake started to erupt, triggering a lava flow which continued for two months . The earthquakes continued, shifting nearer to the city of Shimabara . On the night of 21 May, two large earthquakes were followed by a collapse of the eastern flank of Mount Unzen's Mayuyama dome, causing an avalanche which swept through Shimabara and into Ariake Bay, triggering a tsunami . It is not known whether the collapse occurred as a result of an eruption of the dome or as a result of the earthquakes . The tsunami struck Higo Province (Kumamoto Prefecture) on the other side of Ariake Bay before bouncing back . Out of an estimated 15,000 fatalities, around 5,000 are thought to have been killed by the landslide, around 5,000 by the tsunami across the bay in Higo Province, and a further 5,000 by the tsunami returning to strike Shimabara . The waves reached a height of 330 ft (100 m), making this a small megatsunami . </Td> </Tr>

All tsunamis in recorded history have occurred in the pacific ocean