For at least 2,500 years before the 1860s, the only human presence in the San Jacinto Mountains was provided by Cahuilla (and possibly Luiseño) Indians from the surrounding valleys and foothills. San Jacinto and Tahquitz peaks hold a central place in Cahuilla mythology. Bands of Cahuilla used to camp in the high country each summer and fall, bolstering their winter food supplies by gathering and grinding acorns and hunting small game.
The 1852 Treaty of Temecula would have granted legal ownership of the entire mountain range to the Cahuilla; instead, its rejection by the U.S. Senate, under pressure from California officials, consigned their clans to scattered reservations. Pictographs on boulders and bedrock mortars near oak groves and creeks still testify to their former presence.
The earliest documented European entry to the San Jacinto Mountains came in 1860, after prospectors fanned out across the West in the wake of the California Gold Rush. After an initial press report that year, however, no significant discoveries materialized in these mountains. A flurry of largely fraudulent developments in the 1890s spawned the short-lived boomtown of Kenworthy in Garner Valley. A few mines, such as the Hemet Belle above Garner Valley, remain accessible to hikers today.