Anacostia is also the general name for the part of Washington, D.C. that lies southeast of the Anacostia River, abutting part of the western edge of Prince George's County. Anacostia's population is almost exclusively poor and black, and it is one of the least developed and most dangerous districts of the city.
Around the time of the Civil War, Anacostia was known as Uniontown, and was mostly a white and working-class suburb of downtown DC, one of the city's first. During the Reconstruction period, it saw a gradual influx of freed slaves, generally the more well-off of that group, including Frederick Douglass, Anacostia's most famous historical inhabitant, who was sometimes called the "Sage of the Anacostia". Until the 1950s, the District's period of most rapid growth, Anacostia mostly consisted of proto-suburban single-family dwellings, and was racially mixed. It was never the most prosperous part of the city, or the best to live in, particularly for blacks who were stuck with the poorly funded and overloaded part of the segregated school system, but it was largely above average.
However, two waves of migration, first of the white population to the outlying suburbs, and then of middle and upper class black professionals to Prince George's County and better downtown neighborhoods west of the Anacostia River, left the demographics drastically shifted. By the 1970s, Anacostia was 95% black and the poorest part of the city.
The city's response was to zone massive chunks of Anacostia for giant subsidized apartments complexes, and build a series of housing projects. A number of large public facilities like mental hospitals and sewage treatment plants were also built east of the river, partly in the hopes of them creating jobs, but mostly just to put them in an area of the city that was already seen as out-of-the-way and undesirable.
Anacostia reached its nadir in the late '80s, during D.C.'s ruinous crack epidemic. Basic public services became unreliable or non-existent, gangs ruled the streets, and much of the city-provided housing was literally uninhabitable. The utter and complete breakdown in the basic medical and sanitation systems even led to several outbreaks of diseases like tuberculosis and cholera that one associates more with the Third World than the capitol of the United States.
Today, Anacostia seems to have entered a period of relative recovery. The city of DC is being redeveloped and rediscovered as the pendulum slowly swings back from the suburbs, and the addition of the Metro's Green Line has made it easier for residents to travel to jobs outside of Anacostia, and non-residents to come in. It's a sad statement on DC's history that one of the best things one can say about Anacostia is that it's no longer a living hell, but this is still a big step. | 
