White flight, also known as white exodus, refers to the sudden or gradual large-scale migration of white people from areas becoming more racially or ethnoculturally diverse to more racially homogenous suburban or exurban regions. The term has more recently been applied to other migrations by whites from older, inner suburbs to rural areas, as well as from the American Northeast and Midwest to the milder climate in the South and West. The term 'white flight' has also been used for large-scale post-colonial emigration of whites from Africa, or parts of that continent, driven by levels of violent crime and anti-colonial or anti-white state policies. Starting in the 1950s and 1960s, the terms became popular, especially in the United States.