The system of segregation in the Old South, instituted in the years following Reconstruction, as the nominal losers of the Civil War regained control of their local politics. Forerunner to South Africa's apartheid by many decades, and it took
decades of legislation and court rulings in the US before it could be reversed; the echoes are harder to remove. Two "separate but equal" societies - separate schools, restaurants, water fountains, businesses... Chicken-wire borders... "Niggertown"...