History 22 Politics and government 10 Presidents 6 Social conditions 5 Singers 4 Slavery 4 Black people 3 more ... Conservationists 3 Deforestation 3 Enslaved persons 3 Naturalists 3 Social aspects 3 Actresses 2 Bishops 2 Control 2 Diplomats 2 Drug dealers 2 Drug traffic 2 Economic conditions 2 Educators 2 Fame 2 Landscape architects 2 Motion picture actors and actresses 2 Natural history 2 Organized crime 2 Political aspects 2 Political persecution 2 Political prisoners 2 Rain forest conservation 2 Rubber tappers 2 less ...