The five cities bidding to host the 2012 Olympic Games put forward their final pleas to win the vote in Singapore on Wednesday.
Lord Coe fronted London's final presentation, backed by messages from Tony Blair and the Queen.
Paris, who had been the favourite to win throughout, New York, Moscow and Madrid also put forward their cases to the International Olympic Committee.
IOC members then selected their preferred option in a lengthy vote.
Coe, who claimed London had rehearsed its final presentation to "within an inch of their lives", said the young worldwide were the key to its bid.
The former Olympic champion said: "London's vision is to reach people, young people, all around the world and connect them with the power of the Games.
"We want to deliver a magical experience and an electrifying atmosphere for competitors and spectators to provide the uplifting sporting occasion which distinguishes the Olympic Games from other sporting events."
Coe's sentiments were backed by Blair and the Queen, whose message of support was read out by Princess Anne.
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Blair, who headed back to Britain for the G8 summit in Scotland after spending 48 hours lobbying alongside the bid team in Singapore, said in a recorded message: "My entire Government and the main opposition parties are united behind this bid. It's the nation's bid and it has united people across the country."
Paris got the final presentations under way at 0200 BST courtesy of Mayor Bertrand Delanoe and French President Jacques Chirac, followed by a lengthy video from French director Luc Besson, famous for films such as Leon and the Big Blue.
Delanoe finished by saying: "Paris needs the Games, Paris wants the Games, Paris loves the Games."
An impassioned Chirac added: "The heart of Paris and the heart of France are beating in unison in the hope of becoming Olympic ground in 2012."
Senator Hillary Clinton and New York mayor Michael Bloomberg, plus former Olympians Bob Beamon and Muhammad Ali, took the stage for their city's bid on Wednesday.
Clinton said: "We are 100% committed to making the 2012 Games a truly spectacular event."
Bloomberg highlighted New York's ability to recover from the terrorism attacks of 11 September in summarising the city's presentation.
"New Yorkers asked ourselves 'can we recover', 'will we rebuild'?" he said. "Without hesitation, New Yorkers stood up and said 'yes'. This spirit will be given to your Games."
Moscow was the third bidding city to address the IOC members, with arguably the highlight of their 45-minute allocation a video speech from President Vladimir Putin.
French President Jacques Chirac put forward Paris' case
Putin gave his "absolute endorsement" to Russia's presentation, which ended with shouts of "Moscow, Moscow" from within the convention centre.
"The Games, if held in Moscow, would be the best in the history of the Olympic movement," added Putin.
Madrid completed the presentations by focusing on the success of the 1992 Games Spain hosted in Barcelona.
Queen Sofia hailed their 2012 efforts as a "very special time for me and the Spanish royal family".
And she added: "Madrid 2012 has the whole-hearted support of the people of Spain. We look forward to seeing you in Madrid."