August 5, 1783 Eruption of Asamayama

466 killed by Kamabara pyroclastic flow. 93 people who were able to climb up steps of small temple survived. Hot mudflows from the Kamabara nuee flowed into the Agatsuma R, causing a temporary dam. Flood downstream over a distance of 100 km washed away 1,300 houses and up to 1,400 people. Suspended ash and dust decreased sunlight, and resulting cold and rainy weather caused a famine in the Kanto region. Approximately 300,000 people dies in northern Japan from the Tenmei famine, which lasted from 1783-1787. Some estimates suggest up to 1 million deaths, then about 3% of Japan's population, but the eruption is considered only a contributing factor. (reference #9675)

August 5: Tenmei eruption. The Azuma pyroclastic flow and Kanbara debris avalanche reached the northern foot of the volcano, turning into lahar downstream and blocking the Azuma River, which then washed out and swept away villages in the Tone River basin. After the Kanbara pyroclastic flow, the Onioshidashi lava flowed down the northern slope. 1,151 people were killed, 1,061 houses were swept away, 51 houses were burned down, and over 130 houses destroyed. (reference #12936)