Britain's Queen Elizabeth declared the London Olympics open after playing a cameo role in a dizzying ceremony designed to highlight the grandeur and eccentricities of the nation that invented modern sport.
Children's voices intertwining from the four corners of her United Kingdom ushered in an exuberant historical pageant of meadows, steel mills and megapixels before an audience of 60,000 in the Olympic Stadium and a probable billion television viewers around the globe.
Many of them gasped at the sight of the 86-year-old queen, marking her Diamond Jubilee this year, putting aside royal reserve in a video where she stepped onto a helicopter with James Bond actor Daniel Craig to be carried aloft from Buckingham Palace.
A film clip showed doubles of her and Bond skydiving towards the stadium and, moments later, she made her entrance in person.
"Great Britain was the cradle of modern sport," International Olympic Committee President Jacques Rogge told reporters. "You invented modern sport in the second half of the 19th century."
To underline the point, Bradley Wiggins, crowned five days earlier as Britain's first winner of the Tour de France and hoping to add more road cycling gold in London, tolled the world's largest tuned bell to begin the ceremony.
David Beckham, the English soccer icon who helped to convince the IOC to grant London the Games, sped down the Thames in a speedboat bearing the Olympic flame on the penultimate leg of a torch relay that inspired many ordinary people around Britain.
And in one moment of simple drama, the stadium fell silent as five giant, incandescent Olympic rings, symbolically forged from British steel mills, were lifted slowly out of the stadium by weather balloons, destined for the stratosphere.
More than 10,000 athletes from 204 countries will compete in 26 sports over 17 days of competition in the only city to have staged the modern Games three times.
Most of them were there for the traditional alphabetical parade of the national teams, not least the athletes from Egypt, Tunisia, Libya and Yemen competing in their first Olympics since their peoples overthrew autocrats in Arab Spring revolutions.
Brunei and Qatar were led in by their countries' first ever female Olympians and so, along with Saudi Arabia, ended their status as the only countries to exclude women from their teams.
At a reception earlier in the day, the queen spelled out the role played by her family after the Olympics were revived in Athens in 1896.
"This will be the third London Olympiad. My great grandfather opened the 1908 Games at White City. My father opened the 1948 Games at Wembley Stadium. And, later this evening, I will take pleasure in declaring open the 2012 London Olympic Games at Stratford in the east of London," she said.
"Over recent months, many in these islands have watched with growing excitement the journey of the Olympic torch around the United Kingdom. As the torch has passed through villages and towns, it has drawn people together as families and communities.
"To me, this spirit of togetherness is a most important part of the Olympic ideal. And the British people can be proud of the part they have played in keeping the spirit alive."
The opening show, costing an estimated 27 million pounds ($42 million), was inspired by William Shakespeare's play "The Tempest", his late-life meditation on age and mortality.
Children were centre-stage throughout, starting from the moment when live pictures of junior choirs singing in the landscapes of England, Scotland, Wales and Northern Ireland were beamed into the stadium's giant screens, four traditional songs woven together into a musical tapestry of Britain.
Oscar-winning film director Danny Boyle began his sweep through British history by grassing over the arena in a depiction of the pastoral idyll mythologised by the romantic poet William Blake as "England's green and pleasant land".
Idyll turned swiftly to inferno as the Industrial Revolution's "dark Satanic mills" burst from the ground, before those same mills forged the last of five giant rings that interlocked and were carried aloft by balloons.
Many sequences turned the entire stadium into a vast video screen made up of tens of thousands of "pixels" attached to the seats. One giant message, unveiled by Tim Berners-Lee, British inventor of the world wide web, read "This is for Everyone".
The performance included surreal and often humorous references to British achievements, especially in social reform and the arts, and was due to conclude with a performance by former Beatle Paul McCartney.
Until the last few days, media coverage had been dominated by security firm G4S's admission that it could not provide enough guards for Olympic venues. Thousands of extra soldiers had to be deployed at the last minute, despite the company's multi-million-dollar contract from the government.
Counter-terrorism chiefs have played down fears of a major attack on the Games, and Prime Minister David Cameron said that a safe and secure Olympics was his priority.
Suicide attacks on London on July 7, 2005, the day after London was awarded the Games, killed 52 people. This year the Games will mark the 40th anniversary of the 1972 Munich massacre, when 11 Israeli Olympic team members were killed by Palestinian militants.
"This is the biggest security operation in our peacetime history, bar none," Cameron said, "and we are leaving nothing to chance."
Although no medals will be awarded until Saturday, the women's soccer tournament started on Wednesday, and on Friday South Korean archers set the first world records of the Games.
Im Dong-hyun, who suffers from severe myopia and just aims at "a blob of yellow colour", broke his own 72-arrow world record with a score of 699 out of a possible 720, leading his two colleagues to a record combined score as well.
The Games' first medals will be decided in the women's 10 metres air rifle final on Saturday, with the big action coming in the men's cycling road race, where world champion Mark Cavendish is favourite to become Britain's first gold medallist.
In the evening, Americans Michael Phelps and Ryan Lochte are scheduled to line up for a classic confrontation in the men's 400 metres individual medley final.
Phelps, competing in seven events after winning a record eight gold medals four years ago in Beijing, is bidding to become the first swimmer to win gold in the same discipline three times in a row.
"This is going to be a special race," said Gregg Troy, head coach of the American men's team. "I can't imagine a better way to promote our sport than a race like this on the first day."