The Oshima–Ōshima eruption arose from the volcanic island located in the Izu Islands, Japan, characterized by its geological volatility. As volcanic activity escalated, the eruption released vast amounts of ash and pyroclastic material. This violent geological phenomenon subsequently generated a tsunami of extraordinary scale, with waves reaching far inland along the Japanese coastal territories. The tsunami's force was propelled by the collapse of the volcanic structure and the displacement of ocean waters, creating a formidable threat to nearby populations.

Coastal fishing villages, unaware of the imminent danger, were quickly overwhelmed by the surging waters. The tragedy led to the loss of at least 2,000 lives, representing a significant portion of the local populace. Survivors of the tsunami struggled with the aftermath, dealing not only with loss and destruction but also with the challenge of rebuilding their communities under uncertain future geological threats. The event illustrated both the raw power of nature and the vulnerabilities of human settlements on coastlines prone to such natural disasters.

In addition to the immediate consequences, the eruption and tsunami prompted further studies on volcanic activity and tsunami formation, which later influenced disaster preparedness and response strategies in Japan. The event serves as a critical case study in understanding the interplay between geological phenomena and their socio-economic impacts on coastal communities.