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‘Devil in the thicket’ gave mountain its name

Written by Beverly Lane in the Valley Pioneer as a “Valley Vignette” on August 12, 1987

A mountain of such prominence had to be named, and the Spanish were never reluctant to do so.  In addition to the Indian ones, Mount Diablo had other names before the battle ocurred which first introduced the name “Mount Diablo.”

Historian Erwin Gudde, states that the earliest name was apparently “San Juan Bautista,” evidently in honor of Juan Bautista de Anza who led an expedition around the mountain in 1776.

In the early 1800s the name “Sierra de los Bolbones” was used most frequently by Californians and explorers. In October 1811 Father Ramon Abella of San Francisco and Father Fortuni of San Jose explored the Delta and wrote down the name “Cerro Alto de los Bolbones” for the first time.

This title referred to the Volvon Indian tribe which lived north and east of the mountain.  Other Spanish writers spelled the Indian name Golgone, Bolbone or Volvone.

In the summer of 1805 a battle occurred from which the name “Monte Diablo” can be traced.  At first it was not attached to the mountain at all but to a thicket or “monte” in Spanish.

That year a military expedition from the San Francisco presidio, led by Luis Arguello, was sent to pacify the Bay Area’s inland valleys. Indians in these valleys had changed from the peaceful natives early diarists described and were aggressively resisting Spanish efforts to bring them to the missions.

In one protracted battle, the Spanish pursued Indians to a thicket of willows, close to a Chupcan village, located in today’s north Concord. When darkness set in, Arguello decided not to follow them into the thicket which was familiar territory to the Indians.

In the night the Spanish reported lights moving and strange noises – and next morning the natives were gone.  According to historian F.J. Hulaniski in 1917, “The lights were probably produced by a phosphorescence which the troops did not understand.”

The soldiers dubbed the area Monte Diablo (Thicket of the Devil) because the experience had so unnerved and frightened them. To the illiterate and devout Catholic soldiers, the devil was a real feature of their lives with all kinds of power, including the ability to change its form at any time.

The first regular mentions of the name “Diablo” appeared in the 1820s.  About 1824 the name “M. del Diablo” was written on the Plano Topografico of Mission San Jose.  It was drawn by Father Narciso Duran of that mission and referred to a Chupcan Indian village near today’s Highway 4.

In 1828 the name was given to the “Monte del Diablo” land grant for which Salvio Pacheco applied the year earlier.  It was mentioned also by explorer Edward Belcher of the H.M.S. Sulphur in 1837. When he wrote about the expedition, he spoke of the “high range of the Montes Diavolo” as well as the “range of the Sierra Bolbones… visible equally from the sea.”

By the 1840s the name occurred regularly in the travel literature. The 1841 Charles Wilkes expedition was impressed: “The scenery was very much admired, and Mount Diavolo, near the mouth of the San Joachim, adds to its beauty.”

The Fremont map of 1848 called the mountain Monte Diabolo and, in 1844, Eugene Duflot de Mofras wrote, “Mount Diablo, the highest peak in the California range actual height is 1,149 meters.  The end of this chain is designated locally as Sierra de los Bolbones.  The location of Mount Diablo is important to navigators; being visible from afar it marks the entrance to San Francisco Harbor.”

Eventually the name shifted from a thicket in north Concord to the smaller of the mountain’s two peaks.  American explorers and new settlers, mistaking the name “monte” for “mountain,” began to apply the title to the whole mountain.  Old-timers insisted that only the north peak should by labeled Diablo and called the mountain Sierra de los Bolbones instead.

The next Valley Vignette looks at the legends which developed once the mountain was named for the devil.


Resources: Erwin G. Gudde, California Place Names;  Robert F. Heizer in Geologic Guidebook of the San Francsico Bay Counties, 1951; J. F. Hulaniski, History of Contra Costa County, 1917; Randall Milliken, A Time of Little Choice, 1995; Richard A. Pierce, H. M. S. Sulphur at California 1837 and 1839, 1969; Charles Wilkes, Narrative of the United States Exploring Expedition During the years 1838, 39, 40, 41, 42, 1845.