Which Brazilian city has been the country's second-most populous since 1960?

Which Brazilian city has been the country’s second-most populous since 1960? Rio de Janeiro. São Paulo overtook it in 1960, leaving Rio de Janeiro as Brazil’s second-most populous city.

Rio was founded by the Portuguese in 1565 beside Guanabara Bay. It became the capital of colonial Brazil in 1763 and later served as the capital of the Portuguese court, the Empire of Brazil, and the Brazilian Republic. That national-capital role ended in 1960, when Brasília was inaugurated in the country’s interior.

The question concerns the municipality, not the broader metropolitan region. Rio’s urban area is much larger than the city proper, and population rankings can change depending on whether a source counts municipal boundaries, continuous urbanization, or metropolitan areas. On the standard city-proper comparison, however, Rio remains behind São Paulo and ahead of Brazil’s other municipalities.

The most frequent confusion is with Brasília: Brasília became the national capital in 1960, but it is not Brazil’s second-most populous city. Another is treating Salvador or Fortaleza as the long-standing number two; neither displaced Rio in the relevant ranking.