U.S. Population in 1860

In the last year of Democrat James Buchanan’s one term as president, about 31.4 million people, including slaves, lived in the United States, according to the census of 1860. But only about 2 percent of those people-620,000-lived in the sprawling and largely unsettled West and Southwest. California, with a population of 380,000 (up from about 18,000, not including Indians, before the gold rush), was home to two-thirds of those Americans.