In 1836, Texas settlers broke from Mexico. In 1845, the territory was annexed by the United States to become the twenty-eighth state, a slave state. Then, the following year, President James Polk manufactured a crisis at the Mexican border as pretext to launch a war on Mexico. Fighting lasted two long years, with Mexicans putting up more effective resistance than anticipated. The United States eventually won, taking 55 percent of Mexico’s territory—from Arizona’s desert sands to California’s Pacific beaches to Utah’s winter snows—and turning some hundred thousand Mexican citizens, of all races, into United States subjects.
