Sacramento River massacre
1846 CE.
Shown on the map at 40.585°, -122.374°.
The Sacramento River massacre refers to the killing of many Wintu people on the banks of the Sacramento River on 5 April 1846 by an expedition band led by Captain John C. Frémont of Virginia. Estimates range from 125 to 900.
Text from the Wikipedia article Sacramento River massacre, licensed CC BY-SA 4.0.