Nicolas Sarkozy succeeded Jacques Chirac as French president on Wednesday, promising to usher in an era of change and restore national pride.
At the start of ceremonies mixing republican pageantry and symbolic gesture, Sarkozy was inaugurated under the chandeliers of the Elysee Palace, which will be his home for the next five years following his comprehensive election victory on May 6.
In his first speech in the opulent Salle des Fetes, Sarkozy, 52, vowed not to disappoint the French people.
"I will defend the independence of France. I will defend the identity of France," said the conservative leader, who is the first French head of state to be born after World War Two.
"There is a need to unite the French people ... and to meet commitments because never before has (public) confidence been so shaken and so fragile," he said in an apparent dig at Chirac, a former political mentor with whom he now has strained relations.
He also pledged to put the fight against global warming and the defense of human rights at the heart of his foreign policy.
His first act after his speech was to greet family members, including his wife, Cecilia, who has hardly been seen in public this year fuelling speculation about their marriage.
Following a private lunch, Sarkozy rode in an opentop car up the Avenue des Champs Elysees, escorted by the mounted Republican Guard, and laid a floral tribute at the tomb of the unknown soldier beneath the Arc de Triomphe.
He plunged into the crowd to shake hands with well-wishers before laying wreaths at statues of France's World War One and Two leaders -- Georges Clemenceau and General Charles de Gaulle.
Continuing the national theme, he paid homage to 35 French resistance fighters killed by the Nazis in 1944 before heading off to Berlin to meet Chancellor Angela Merkel in a trip aimed at underscoring the importance of Franco-German relations.
Sarkozy is widely expected to name moderate conservative Francois Fillon as his prime minister on Thursday, and draft centrists and high-profile leftists into a streamlined cabinet which will probably be unveiled on Friday.
Chirac, who ruled for 12 years, met Sarkozy in private to give him the launch codes for France's nuclear strike force. He then drove off into retirement, with Sarkozy applauding and waving goodbye from the Elysee Palace courtyard.
The office he inherits wields more powers than any other elected Western leader.
A 21-gun salute resounded near the tomb of the emperor Napoleon across the river Seine as Constitutional Council President Jean-Louis Debre proclaimed Sarkozy the sixth president of France's Fifth Republic.
"From this day on and for the duration of your mandate, you embody France, symbolize the republic and represent all the French people," Debre said.
Sarkozy inherits a fractured society, dispirited by years of high unemployment, and says he will take a more hands-on approach than his predecessor.
He wants to be judged on his record in trying to revive the economy. He got immediate good news on Wednesday with data showing France's private sector adding jobs at the fastest rate in six years and growth seen picking up in the second quarter.
But unions and students have warned Sarkozy, a law and order hardliner who mixes pro-market economic views and state intervention, not to ram through reform without negotiations.
Looking to reach across political divides, Sarkozy is expected to name Bernard Kouchner, a Socialist former health minister and human rights campaigner, as his foreign minister.