Rio de Janeiro will host South America’s first Olympics in 2016 after beating other bids including an Obama-backed pitch from Chicago.
Rio de Janeiro saw off Madrid in the final round of voting among International Olympic Committee members overnight.
Carlos Osorio, general secretary of the Rio bid, told Reuters: “Overwhelming, spectacular, unbelievable.”
In an astonishing start to the voting, Chicago, the odds-on favourite, went out in the first round, despite receiving unprecedented support from United States President Barack Obama and the first lady.
It was a rebuff for Obama, who had become the first sitting US president to address an IOC session.
Tokyo followed them out in the second round, leaving Madrid and Rio to slug it out in the final round.
Rio will be the first South American city to host the Games.
Nearly 50,000 people erupted in celebration when Rio was announced host, jumping and cheering in a Carnival-like party on Copacabana beach.
Obama was “disappointed” Chicago failed to win its bid but was “absolutely” glad he went to Copenhagen to make a pitch for his hometown, White House spokesman Robert Gibbs said.
“The president is disappointed as you might imagine,” Gibbs told reporters aboard Air Force One as Obama flew back from Denmark.
“The president would never shy away from traveling anywhere, talking to anyone about this country. He is enormously proud of this effort that was made,” Gibbs said, adding the Obamas had “made a case from the heart.”