The Democratic President Polk took office in March, 1845; the Mexican War, beginning in May, 1846, was fought to a successful close in a year and five months, ending September, 1847; the fertile territory of Oregon, purchased from Spain, had been peaceably occupied by rapid immigration and by settlement of disputed boundaries with Great Britain; California—a Mexican province—had been secured to the American settlers of its lovely hills and valleys by the prompt daring of Capt. John C. Fremont; and the result of the war was the formal cession to the United States by Mexico of the territories of California and New Mexico, and recognition of the annexation and statehood of Texas.
Both the North and the South had thus gained large possibilities, and at the North the spirit of enterprise and the clear perception of the economic value of free labor as against slave labor were working mightily to help men see the moral arguments of the antislavery people. The division of interest was becoming plain; the forces of good sense and the principles of liberty were consolidating the North against farther extension of the slave-power. The perils foreseen by Calhoun, which he had striven to avoid by repression of all political discussion of slavery, were nigh at hand. The politicians of the North, too, scented the change, and began to range themselves with their section; and, while there was a long struggle yet ahead before the issues would be made up, to the eye of faith the end was already in sight, and the “Free-Soilers” now redoubled their efforts both in discussion and in political action.