The Bōsō Peninsula was struck by a major tsunami on 4 November 1677, caused by an earthquake at the southern end of the Japan Trench. It was felt onshore with only a maximum of 4 on the JMA intensity scale, but had an estimated magnitude of 8.3–8.6 Mw. The disparity between the maximum intensity and the magnitude estimated from the tsunami suggest that this was a tsunami earthquake. There no records of significant damage caused by the shaking, but the resulting tsunami caused widespread damage and an estimated 569 people were killed