free North before the American Civil War. The American Industrial Revolution, promoted urbanization of what was previously a largely agrarian society Especially as transportation systems have improved over the centuries, it has become relatively easy for many Americans to move from one part of the country to another, given the lack of internal borders and dominance of English in most areas. Many do so for reasons of economic opportunity, climate, or culture. In the 20th century, to seek jobs and escape racial violence, African Americans left the South in the Great Migration and Second Great Migration, moving to Northern, Midwestern, and Western cities, where they had to compete with recent European immigrants. Railroads, promoting migration westwards and streetcar suburbs, created significant ethnic shifts in urban areas. Economics and natural disasters have driven migration, for example during the Dust Bowl, World War II, and since the decline of the Rust Belt Suburbanization period after World War II, with "white flight" to new housing and away from later social unrest, followed by "Black flight" The majority of Native Hawaiians who moved to the mainland U.S. have settled in California. Air conditioning has promoted migration from northern areas to the Sun Belt. The Jet Age promoted vacationing and part-time living in warmer areas (snowbirding). In some cases, immigrants and migrants form ethnic enclaves; in others, mixture creates ethnically diverse neighborhoods. Racial makeup of the U.S. population For demographics by specific ethnic groups rather than general race, see "Ancestry" below. White and European Americans White and European Americans are the majority of people living in the United States. White people are defined by the United States Census Bureau as those "having origins in any of the original peoples of Europe, the Middle East, or North Africa." Like all official U.S. racial categories, "White" has a "not Hispanic or Latino" and a "Hispanic or Latino" component, the latter consisting mostly of White Mexican Americans and White Cuban Americans. As of 2019, White Americans are the majority in 49 of the 50 states (plus Puerto Rico)White Americans are not a majority in Hawaii, the District of Columbia, American Samoa, Guam, the Northern Mariana Islands, and the U.S. Virgin Islands. As of 2019, non-Hispanic Whites are a majority in 44 statesthey are not a majority in California, Hawaii, Maryland, Nevada, New Mexico, Texas, the District of Columbia, American Samoa, Guam, the Northern Mariana Islands, Puerto Rico, and