Expansion of coffee plantations in the state of Rio de Janeiro gave a new impulse to the city’s development. Nobles and bourgeois moved their residences north to the São Cristóvão district. Merchants and English bankers chose to live around the Outeiro da Glória and Praia do Flamengo areas in the south, or they established their residences in the nearby Botafogo and Laranjeiras districts. The French, on the other hand, lived in country houses scattered in the Tijuca area farther westward.

In that era, as Brazil expanded its world export trade in such products as coffee, cotton, sugar, and rubber, the city changed its appearance, and the traces of its colonial past were effaced. In 1829 oxcart traffic was banned from the Rua do Ouvidor, then the city’s most elegant street. In 1838 the first public transportation—horse-drawn buses—began to run to the districts of São Cristóvão, Engenho Velho, and Botafogo. In 1868 the first tramcars, also drawn by animals, were introduced. A steamboat service to Niterói began to operate in 1835. The first railroad was built in 1852 to Petrópolis, and a line reached Queimados in the Nova Iguaçú area in 1858. In 1854 gas replaced oil for street lighting, and wireless telegraphy was inaugurated. Sewerage was installed in 1864, and telephone service began in 1877.

The republican period

When Rio de Janeiro, which had formerly been the capital of the empire, became capital of the republic of Brazil in 1889, it was already a considerable community. At the time of the 1890 census, it had more than 520,000 inhabitants on 61 square miles (158 square km), ranking it as the largest city in Brazil and one of the larger cities in the world. The 1891 constitution designated it the Federal District.

During the federal administration of Pres. Francisco de Paula Rodrigues Alves, from 1902 to 1906, Rio de Janeiro was further transformed. A team of administrators and technicians drained swamps, cleared slums, paved and widened streets, and markedly improved health conditions, notably by reducing cases of yellow fever and smallpox. The central avenue (called Avenida Rio Branco from 1912), still the most important of the Centre, was opened during that period; Avenida Beira-Mar, running parallel to part of the south shore, was built on reclaimed land; and several other important avenues were opened.

The population of the Federal District exceeded 1,000,000 by 1920 and increased to 1,750,000 by 1940. During that period the number of industrial establishments in the Federal District nearly trebled. Castle Hill was demolished, land reclamation increased the area in the Centre, and the first skyscrapers appeared. Streetcar lines, now moved by electrical power, multiplied. While settlement spread on the east coast, some areas to the north lost status—such as São Cristóvão, which became an industrial and lower-class residential neighbourhood.

In the mid-20th century, metropolitan Rio de Janeiro grew beyond its formerly narrow confines because of immigration from other parts of Brazil, as well as a high rate of natural increase. The suburban population more than tripled to some 1.5 million between 1940 and 1960, at a time when the city proper exceeded 3.3 million. Following the transfer of the national capital to Brasília in 1960, Rio’s rate of population growth slowed somewhat, although the suburban population continued to mushroom. By 1980 there were more than 5 million residents in the city and 3.6 million in the suburbs. Although subsequent growth continued at a lesser rate, by the early 21st century the metropolitan population exceeded 11 million, of which nearly half resided in the suburbs.

Beginning in the latter part of the 20th century, population growth, real estate speculation, and an amplified dependence on automobiles precipitated a series of changes in the city. The highway system was expanded, with improved access to numerous suburban areas; still higher skyscrapers arose in the Centre; and larger residential towers increasingly replaced small apartment buildings and houses. Landowners, the industrial sector, and the financial sector favoured the changes; however, higher rents forced many poorer residents to move from the central city to the periphery or to the rapidly expanding favelas on the steeper hillsides. Meanwhile, many affluent families settled in the southwest, notably in Ipanema and Leblon and at sites farther down the coast.

Rio has maintained its status as the second largest manufacturing centre in Brazil, after São Paulo. In addition, Rio’s service sector remains one of the strongest in the country, providing for increasing numbers of jobs in such areas as finance, communications, tourism and entertainment, public and private education, and computer engineering. Rio remains a major centre for cultural exhibitions and international conferences, and many of the more affluent and influential Brazilians keep homes there. Despite desperate conditions in the city’s favelas, as well as high rates of violent crime throughout the city, grave levels of air and water pollution, and myriad other problems, Rio de Janeiro is still widely recognized as one of the world’s more beautiful urban centres.

In 2009 the International Olympic Committee selected Rio as the site of the 2016 Summer Games. It was the first city in South America to be chosen to host the Olympics.