After Mexican independence in 1810, Mexico and the United States had numerous territorial disputes. Political upheaval in Mexico and economic opportunity across the border spurred migration to the United States after the Mexican Revolution. The North American Free Trade Agreement (NAFTA) paved the way to a closer U.S.-Mexico relationship on security, trade, and counternarcotics.
Immigration has been an important element of U.S. economic and cultural vitality since the country's founding. This interactive timeline outlines the evolution of U.S. immigration policy after World War II.