Rio de Janeiro is a place.
Rio de Janeiro ( [ ˈriːoʊ_di_ʒəˈnɛəroʊ , _ - deɪ_ʒə - , _ - də_dʒə - ] [ ˈʁi.u d ( ʒi ) ʒɐˈnejɾu ] ; River of January ) , or simply Rio , is the second-most populous municipality in Brazil and the sixth-most populous in the Americas . Rio de Janeiro is the capital of the state of Rio de Janeiro , Brazil 's third-most populous state . Founded in 1565 by the Portuguese , the city was initially the seat of the Captaincy of Rio de Janeiro , a domain of the Portuguese Empire . Rio de Janeiro subsequently served as the capital of the independent monarchy , the Empire of Brazil , until 1889 , and then the capital of a republican Brazil until 1960 when the capital was transferred to Brasília .