May 21, 1792 Eruption of Unzendake

Reference #9675:

1792, May 21. 14,524 deaths. Figures from Katayama indicate 9,528 fatalities along the Shimabara peninsula and an additional 4,996 fatalities in Higo and Amakusa provinces across Ariake Sea. The vast majority were killed by the tsunami, the avalanche reaching only the southern outskirts of Shimabara city.

Reference #2140:

The eastern part of Maye-yama collapsed to cause an avalanche toward the eastern foot which caused approximately 10,000 casualties in Simabara. Tsunami was produced by this avalanche and killed over 4,300 persons (REF #2140) on the coasts to the east and south of Simabara. The tsunami was caused by collapse of nearly 0.5 km3 of one of the lava domes on Unzen, Mayeyama.

From November 13, 1791, earthquakes, rumblings, and avalanche had taken place, and on February 10, 1792, rock fragments were thrown out from the summit of Hugendake.

On March 1, 1792, when the summit eruption had already stopped, lava began to be extruded from a vent 1 km NNE of the summit, which traveled to a distance of 3 km with a volume of 0.11 cb. km. On March 5, landslide occurred,

and on April 21, about 300 earthquakes were felt, one of which destroyed the houses of Simabata. On May 21, the eastern part of Maye-yama collapsed to cause an avalanche toward the eastern foot which caused 10,000 casualties in

Simabara. Tsunami was produced by this avalanche and killed 4,300 persons on the coasts to the east and south of Simabara. The avalanche, totaling 0.48 cb. km in volume, was caused either by an explosion (I) at Maye-yama or by earthquake shocks.

Reference #1686:

The disaster at Simabara, Japan, and neighbouring coasts on 21 May 1792, which killed more than 15000 people, was

caused by the collapse of nearly 0.5 km3 of one of the lava domes on Unzen Volcano, Mayeyama, situated some 4 km from vents which had been active a month or two previously. The collapse was caused either by an explosion at Mayeyama, or by a strong swarm of volcanic earthquakes. The landslide generated waves which reached a height of 20 to 30 feet (6 to 9 m), causing devastations... for a distance of 77 km.

Reference #1645:

The Shimabara Catastrophe broke out on the Shimabara peninsula, Kyushu, at about 20 o’clock, 21st of May, 1792, according to the present standard time of Japan. More than 14,500 persons were lost by the collapse of Mt. MaCyama (Mayuyama) and tsunami.

Reference #132:

May 21, 1792. Japan, Shimabara in Hizen. Eruption of Mount Unsen accompanied by sea wave.

Reference #414:

In the winter of 1791-1792, there was a strong eruption of Unzen volcano (Nagasaki Prefecture, Kyushu Island), which lasted four months. It did great damage to the vicinity of the volcano and was accompanied by frequent underground shocks, as a result of which homes collapsed here and there. Some people were killed. The side of the mountain collapsed at the end of the eruption, and this caused a destructive tsunami. The accounts of the eruption in the Japanese literature are somewhat contradictory, especially with respect to dates.

Reference #12371:

About 15,000 deaths.