Statisticians are not allowed to count people by their origins, complicating research.
But the postcard vision of France with church steeples perched over a contented populace that's wearing berets and carrying baguettes has been upended in the Seine-Saint-Denis region northeast of Paris.
French kings are buried in the great cathedral of Saint-Denis, the main town, but traditional minorities have become the majority in the region.
A study by Simon puts immigrants and their descendants through the second generation at 75 percent of the city's population. It includes people from French overseas departments (8 percent), who are French but of color. The jobless rate was 16.5 percent in 2009, according to Insee, the national statistics agency. But the economic leaders are in the white minority, Simon said, putting new stress on the notion that immigrants and their children are being successfully assimilated.
In Les Bosquets, the most widespread complaint remains poor public transport and the isolation that keeps Les Bosquets at a distance from mainstream France. It takes nearly 90 minutes to get to Paris.
"They've done everything to keep us closed among ourselves," said a 34-year-old born in France of Algerian parents. "It is they who don't want us to integrate." Like most residents of the projects, the man, who works with a private fire department, refused to identify himself by name.
Discrimination is a fact of life in France for minorities, and a poll by the Ipsos firm published this year in the daily Le Monde showed no sign that that might lessen. A full 70 percent of those questioned felt there were "too many foreigners in France." The finger was pointed, above all, at those of the Muslim faith.