The first part of 1848 was relatively calm, and during that year, Texas Comanches even provided guides for the survey of the route of the new Butterfield (California) trail across southern Texas to El Paso and California. The calm changed suddenly with the California Gold Rush. As thousands of gold-seekers raced west, they needed horses, and the Comanches moved to meet this new demand. Horse raids increased in Texas, but the major target was northern Mexico. Comanche raids struck deep into Coahuila, Chihuahua, Sonora, and Durango, reaching their peak during 1852 when they struck Tepic in Jalisco, south of the border at El Paso. To protect the immigrant routes across the plains, the United States called the "Peace on the Plains" conference at Fort Laramie (Wyoming) in 1851. This was an attempt to end, or at least limit, intertribal warfare by defining boundaries between tribal territories.