General Mariano Guadalupe Vallejo was one of California's most distinguished citizens in the mid nineteenth century. A frontier cosmopolitan and visionary, Vallejo owned vast ranchos in northern California and wielded enormous political power throughout the province. While serving as military governor during Mexican rule, he established an open immigration policy that encouraged and facilitated the American entrada to northern California. Dissatisfied with the remoteness of Mexican sovereignty, Vallejo believed that only the United States could unleash California's untapped economic potential. Not even Vallejo's imprisonment by the unscrupulous John C. Fremont during the Mexican-American War deterred the General's pursuit of a political and economic relationship between California and the United States. Although Vallejo lost all his land to Yankee mortgage holders in the years following the conflict, he never abandoned his faith in the power of American democracy to transform human society. Alan Rosenus's richly textured biography uses primary sources to narrate Vallejo's rise to power, his dominance of northern California, and the expansion of his great land holdings. Included in this chronicle are vivid sketches of colorful historical figures like Fremont, Don Salvador Vallejo, Chief Solano, Thomas Larkin, and many others.