By Caroline Wyatt
BBC News, Paris
On Sunday night, it was a jubilant Nicolas Sarkozy who performed France's traditional presidential victory parade - around the Arc de Triomphe and down the Champs Elysees, to popping champagne corks and the raucous cheers of his staunch supporters.
Royal worked hard to beat the energetic Sarkozy
There is a feeling in Paris tonight that France, as Mr Sarkozy said in his victory speech, has turned "a new page of our history".
"In the republic that I want to serve," he said, "there cannot be rights without obligations. All must have their opportunity, but they must earn it by work, by personal commitment, by belief."
No-one is quite sure what will come next, but there is a sense of relief at a decision finally made, even if it is mingled with a fear of the future under its new leader, who has promised change and reform.
France's new president is a man best known for his energy and his will to power: a human dynamo, who left his opponents trailing and exhausted in his wake.
The Socialist Segolene Royal worked hard to beat him, but without the real backing of her own party and without a clear manifesto for France, she failed.
The 52-year-old Nicolas Sarkozy scandalised the Paris elite a few years ago when he admitted to constantly thinking about becoming French president, "not only when I am shaving in the morning".
Yet he was never part of that elite. He is the son of a Hungarian immigrant, who abandoned the young Sarkozy and his two brothers when they were young. According to several biographers, this left him with a burning desire to prove himself through sheer hard work and merit.
Nor did Mr Sarkozy attend the traditional elite school, ENA, but studied instead as a lawyer.
Sarkozy is a deeply divisive figure for the French
He went almost immediately into politics at the age of 22, becoming mayor of the upmarket Paris suburb of Neuilly at just 28 with the aid of the UMP's predecessor, the RPR - the party of President Jacques Chirac, who took the young Nicolas under his wing.
Today, Mr Sarkozy's enemies on the left mockingly call him an American neo-con, who just happens to have a French passport, or deride him as a short, power-hungry man with a Napoleon complex.
His supporters, however, claim with fervour that he is the only man who can save France from its economic and social ills.
What is clear is that the former interior minister - known for his tough stance on crime and illegal immigration - is a deeply divisive figure for the French, thanks partly to his un-ministerial language in 2005.
At the time, he re-assured a woman on one housing estate that he would hose the "scum" or "racaille" from the streets, and helped set France alight during the riots.
'Danger to democracy'
But French voters have decided that his brand of tough leadership is exactly what France needs to reform this ailing nation after 12 long years under Jacques Chirac, who later became Mr Sarkozy's implacable enemy.
In the long battle between the two, Mr Sarkozy finally won his gamble, taking both Mr Chirac's UMP party and now the presidency from his former backer.
In 2005, Sarkozy's un-ministerial language helped set France alight
During the campaign, the Socialists tried to scare the French planning to vote for Mr Sarkozy, by warning that he was a danger to democracy and an aggressive politician who could not be trusted to keep his cool as president.
It was a tactic that clearly backfired.
Christine Lagarde, France's imperturbable and elegant trade minister, insists that image is a political fabrication.
"He's a man of action, who wants to get things done, who is driven," she says.
"France has many politicians with a lot of good ideas, but very few with the passion to act on them. He has real passion. It's what some people refer to as brutality, but he's a very passionate individual who is engaged in finding better solutions for this country."
Mr Sarkozy's former campaign manager, Franck Tapiro has known him for 22 years and says the new president's talents will change the face of France.
"He's a courageous man who has the guts to act and fulfil his promises. He believes that politics can change lives," he enthuses. "He is very dynamic, and for him life is about movement. He's the locomotive and always one step ahead - you just have to follow him."
However, Mr Tapiro acknowledges: "You either love him or you hate him. There is nothing in between."
In his recent head-to-head debate against Ms Royal, Mr Sarkozy very clearly set out his priorities and vision for France.
"France's moral crisis has a name. It is a crisis of work," he told the 20 million French voters watching.
"I want the workers to be respected. I want to protect the French from seeing their jobs going abroad. I don't believe in living on social welfare. I don't believe everyone is the same. I believe in merit, I believe in effort and reward for that effort and I believe in social mobility. But above all, I believe in hard work."
Jacques Chirac leaves behind him a stagnating economy
With that almost Thatcherite rhetoric, Mr Sarkozy has made putting France back to work top of his agenda.
The 74-year-old President Chirac leaves behind him a stagnating economy, unemployment at 9%, and even higher among the young, with some 25% of the under-24s out of work.
So Mr Sarkozy has promised to make the 35-hour working week a minimum rather than a maximum, calling it one of France's most poisonous legacies. He also wants to encourage wealth creation and bring down the number of French bureaucrats.
He is a clear admirer of the Anglo-Saxon work ethic and of the US. On Europe, Mr Sarkozy is in favour of a mini-Constitutional Treaty to be ratified by the French Parliament, rather than risk another referendum. And like most French, he doesn't want Turkey in the EU.
As for key alliances, he said in an interview with Paris Match that his first visit would be to Berlin, then Brussels, America and Africa. He didn't mention Britain.
Mr Sarkozy was, though, the only candidate to campaign for the French vote in London, seeking to woo the young back to France, and winning 40% of the vote there in the first round.
So would his foreign policy differ all that much from Jacques Chirac's? Government spokesman and minister Jean-Francois Cope believes not.
"There will be a large continuity on many questions, such as Iraq," he says. "And that is true for other big issues where France is involved. Then I would say it's a question of generation, of sensibility. Of course they will be different - Mr Sarkozy is 52, part of a younger generation of politicians."
Yet, as leader of one of Europe's most stubborn and unpredictable nations, will Mr Sarkozy really be able to institute the reforms he has promised if the trade unions and others take to the streets in protest?
Political analyst Gerard Grunberg of Sciences-Po University in Paris wonders if he will be able to fulfil the promises made during the election campaign.
"He's a very good politician on TV - part of a new generation of media leaders, like Tony Blair was 10 years ago," he says. "He was able to convince the French that he incarnated movement and change. At the same time, he promised he would protect people, so they felt secure.
Sarkozy wants to harness the talent France lost during years of stagnation
"The French people are contradictory about that - we don't want change because we are really frightened by the future. But another part of us acknowledges that maybe we will have to change."
Nicolas Sarkozy will certainly need to try to unite this fractious, divided and uncertain nation, which fears it has lost its dominant role on the world stage.
However, the new French president remains a divisive figure. As interior minister, he took a hard line on uncontrolled immigration and talked frequently during the campaign of the need to instil French values via a Ministry of National Identity.
This made some in the multi-ethnic French suburbs feel uncomfortable and excluded - although many of immigrant origin agree vehemently with his idea of advancement on merit, rather than family ties or the elite background demanded by many leading French employers.
Unlike many French politicians, Mr Sarkozy has long been a straight-talker, even if it did get him into trouble during the riots - and may again in the future.
However, as president, he is well aware that his job is to unite the nation and act as the almost regal head of state the French expect from their leadership in the Elysee Palace, as well as kick-starting the reforms he has long promised.
Above all, Mr Sarkozy is determined to lead a nation that is able to entice back and put to use all the talent and the energy that France has lost over the past 12 years of stagnation.