A number of the Pomo, an indigenous people of California, had been enslaved by two settlers, Andrew Kelsey and Charles Stone, and confined to one village, where they were starved and abused until they rebelled and murdered their captors.
[6] Kelsey and Stone purchased cattle running free and grazing rights in Big Valley from Salvador Vallejo in 1847.
[7] In the fall of 1849, Kelsey forced 50 Pomo men to work as laborers on a second gold-seeking expedition to the Placer gold fields.
Knowing they would be punished, (Chief) Augustine's wife poured water onto the two men's gunpowder, rendering it useless; Pomo warriors attacked the house at dawn, immediately killing Kelsey with an arrow.
Stone jumped out a window and tried to hide in a stand of willow trees, but Augustine found him and killed him with a rock.
The soldiers under Davidson's command arrived "with orders to proceed against the Clear Lake Indians, and exterminate if possible the tribe.
The one placed by the Native Sons of the Golden West on 20 May 1942 on Reclamation Road 0.3 miles off Highway 20, describes the location as the scene of a battle between U.S. soldiers under "Captain" Lyons and Indians under Chief Augustine.
427, describing the location as the scene of a massacre mostly of women and children, was placed on Highway 20 at the Reclamation Road intersection on 15 May 2005 by the State Department of Parks and Recreation in cooperation with the Lucy Moore Foundation,[4] a non-profit organization founded to educate the California public about the massacre.
[11] A 2015 article in Genocide Studies and Prevention analyzed how this plaque reflects on the massacre and its remembrance by both Native and colonial people.