In 1831, twenty thousand Europeans migrated to the United States; in 1854, that number had risen to more than four hundred thousand. While two and a half million Europeans had migrated to all of the Americas between 1500 and 1800, the same number—two and a half million—arrived specifically in the United States between 1845 and 1854 alone. As a proportion of the U.S. population, European immigrants grew from 1.6 percent in the 1820s to 11.2 percent in 1860.
