Before the arrival of the Spanish, the valley was visited and may have been occupied by Chiricahua Apache. Beginning in about 1775, the Mexican government promoted a policy of Indian appeasement that reduced hostilities. By the early 1800s there were a number of Mexican rancheros in the area that managed thousands of cattle on the open range. As a result of the Mexican War of Independence, the settlers in the northern regions lost the government's protection. Apaches stole or killed most of the cattle, and the settlers who didn't return to the interior of Mexico were killed. By about 1840 the only evidence of their former presence were some ruins and a few herds of wild cattle. The California Gold Rush that began in 1849 drew a large number of people through the area, but by this time only the Apache occupied the area.