A favela (Portuguese pronunciation: [faˈvɛlɐ]) is a slum in Brazil within urban areas. The first favelas appeared in the late 19th century and were built by soldiers who had nowhere to live. Some of the first settlements were called bairros africanos (African neighbourhoods). Over the years, many former enslaved Africans moved in.
Even before the first favela came into being, poor citizens were pushed away from the city and forced to live in the far suburbs. However, most modern favelas appeared in the 1970s due to rural exodus, when many people left rural areas of Brazil and moved to cities. Unable to find places to live, many people ended up in favelas. Census data released in December 2011 by the Brazilian Institute of Geography and Statistics (IBGE) showed that in 2010, about 6 percent of the Brazilian population lived in slums. This means that 11.4 million of the 190 million people that lived in the country resided in areas of irregular occupation definable by lack of public services or urbanization, referred to by the IBGE as "subnormal agglomerations".
The term favela was coined in the late 1800s. At the time, soldiers were brought from the conflict against the settlers of Canudos, in the Eastern province of Bahia, to Rio de Janeiro and left with no place to live. When they served the army in Bahia, those soldiers had been familiar with Canudos's Favela Hill – a name referring to favela, a skin-irritating tree in the spurge family (Cnidoscolus quercifolius) indigenous to Bahia. When they settled in the Providência [Providence] hill in Rio de Janeiro, they nicknamed the place Favela hill from their common reference, thereby calling a slum a favela for the first time.
The favelas were formed prior to the dense occupation of cities and the domination of real estate interests. Following the end of slavery and increased urbanization into Latin America cities, a lot of people from the Brazilian country-side moved to the big city of Rio. These poor and new migrants sought work in the city but with little to no money, they could not afford urban housing. In the 1920s the favelas grew to such an extent that they were perceived as a problem for the whole society. At the same time the term favela underwent a first institutionalization by becoming a local category for the settlements of the urban poor on hills. However, it was not until 1937 that the favela actually became central to public attention, when the Building Code (Código de Obras) first recognized their very existence in an official document and thus marked the beginning of explicit favela policies. The housing crisis of the 1940s forced the urban poor to erect hundreds of shantytowns in the suburbs, when favelas replaced tenements as the main type of residence for destitute Cariocas (residents of Rio). The explosive era of favela growth dates from the 1940s, when Getúlio Vargas's industrialization drive pulled hundreds of thousands of migrants into the (actually old) Federal District, until 1970, when shantytowns expanded beyond urban Rio and into the metropolitan periphery.