In a hotly-contested presidential campaign he fought an intriguing contest with Socialist candidate Segolene Royal.

As a highly combative interior minister and UMP leader he has sharply divided opinion in France - not least by adopting a tough stance on immigration.

He famously described young delinquents in the Paris suburbs as racaille, or "rabble".

That blunt comment - made before the 2005 riots - encouraged some critics to put him in the same category as far-right leader Jean-Marie Le Pen.

Sarkozy, 52, pushed through measures to curb illegal immigration - including deportations - and to integrate skilled migrants into French society.

But he has also advocated positive discrimination to help reduce youth unemployment - a challenge to those wedded to the French idea of equality. His call for state help for Muslims to build mosques was also controversial.

Correspondents say that one of the big questions now is whether he will be able to temper his abrasive style to play the traditional unifying role of the president of France.

Unlike most of the French ruling class, Sarkozy did not go to the Ecole Nationale d'Administration, but trained as a lawyer.

The son of a Hungarian immigrant and a French mother of Greek Jewish origin, he was baptised a Roman Catholic and grew up in Paris.

One of his main political influences is not French but British, according to his other biographer, Nicolas Domenach.

Sarkozy has called for "a rupture with a certain style of politics", saying he wants to encourage social mobility, better schools and cuts in public sector staff.

He served as mayor of the affluent Paris suburb of Neuilly from 1983 to 2002, then became interior minister. He also had a brief spell as finance minister in 2004.

"He's hyperactive, he's ambitious, he's a heavy worker, a workaholic, he never rests," says Anita Hausser, who wrote a biography of Sarkozy and is political editor at the French broadcaster LCI.

It seems that rather than a new ideology, he is a pragmatist who will use any solution as long as it works, the BBC's Caroline Wyatt in Paris says.