Although proclaimed part of New Spain as early as 1542, California became a field for Spanish colonization only in the late 18th century when Franciscan friars, led by Father Junipero Serra, established a series of missions on the coast between San Diego and San Francisco. Father Serra’s priests attempted to convert the Indians to Christianity and teach them to become farmers and herders. In the process however, they imposed a new, alien and strictly regulated life-style, which undermined tribal culture. After Mexico became independent from Spain in 1821, the Mexican government began secularizing the missions and between 1833 and 1840, it parceled out the mission ranches to political favorites. The wealthy rancheros raised cattle, tended by vaqueros (cowboys), and sold hides and tallow to merchant ships from New England — a trade vividly described in Richard Henry Dana’s 1846 classic, Two Years Before the Mast. Lured by favorable publicity about the area, including John C. Fremont’s glowing reports of his expeditions, Americans began settling in California in the 1840s. Although numbering only about 700, they were soon toying with thoughts of independence and California’s annexation by the U.S. — ambitions promptly realized when rumors of the outbreak of the Mexican War in 1846 prompted the Bear Flag Revolt.