U.S. political concept popular in the 1840s.
Inspired by European youth movements of the 1830s (see Young Italy ), the U.S. group was formed as a political organization in 1845 by Edwin de Leon and George H. Evans . It advocated free trade, expansion southward into the territories, and support for republican movements abroad. It became a faction in the Democratic Party in the 1850s. Sen. Stephen A. Douglas promoted its nationalistic program in an unsuccessful effort to compromise sectional differences.