When Julius Caesar marched his legions into Gaul in 58BC, he found a surprisingly coherent federation of barbarian tribes. They had a common religion - Druidism - and the sort of traditions and institutions that allowed vast armies to be marshalled at short notice. Two millenniums before the TGV (train à grande vitesse), the Gauls' high-speed chariots and expressways were the envy of the civilised world. Fine wines and luxury goods were transported safely over vast distances, and a Latin-speaking merchant with a basic grasp of Gaulish could made himself understood from the Mediterranean to the North Sea.

Reading Robert Gildea's sober, concise and masterly history of France from 1799 to the first world war, one is tempted to ask: where did it all go wrong? Or, to put it less frivolously, why, after 2,000 years, did so many educated Frenchmen look back wistfully on the good old days of Vercingetorix, when a patriotic army of handsome, hairy Gauls could inflict a crushing defeat on Caesar's legions?

There was a time, not long ago, when histories of France told a cheering tale of gradual progress - with the occasional catastrophic hiccup - towards a democratic and economically buoyant republic. The revolution (referred to in the singular as though there had been only one) was the blood bath in which feudalism perished. The inevitable mess was tidied up by Napoleon and his legislators; the monarchy was restored, but tempered with a measure of democracy. To the disgruntled majority who were not rich enough to qualify as voters, prime minister François Guizot retorted, “Get rich!” Inveterate anarchists and barricade builders were finally stamped out in 1851 by Napoleon's nephew, who conducted a coup d'état and turned Paris into the world's favourite tourist destination. This was the Second Empire (called “second”, in French, rather than “deuxième“ because “second” is used when there is no further item in the sequence). It ended in defeat by Prussia in 1870, but the economy recovered and the centenary of the revolution was triumphantly marked in 1889 by the erection of a 1,063ft tower of iron girders by the banks of the Seine.

Children of the Revolution tells a very different tale. Far from saving the nation from anarchy, Napoleon left it more deeply divided than before. Brittany and the Vendée had suffered what some historians have termed “genocide”. In the Gard department around Nîmes, which Gildea calls “the Ulster of France”, Protestants were massacred by Catholics. Vast tracts of land were ruled by brigands, and some of the larger cities were effectively independent states.

Long after the revolution of 1789, Paris struggled to impose its civilising influence on the provinces. In much of the country, French was a minority language until the 20th century. For Stendhal, writing in the 1830s, the “civilised part of France” lay north of a line from Nantes to Dijon. All the rest was mired in barbarism: “There they believe in witches, can't read and don't speak French.” Seventy years later, popular guidebooks were still warning tourists who ventured beyond the cities not to talk to the natives. It was to enable car drivers to avoid contact with incomprehensible local tribes that Michelin sponsored a petition in 1912, asking the government to erect signposts all over France.

Paris itself was hardly a model of orderliness. One of Gildea's most telling phrases concerns the constitutional monarchy that was founded by the revolution of 1830: “There was no fighting in the streets of Paris between 1839 and 1848.” Apparently, this represented “an enviable level of stability”. The second part of his two-part history begins in 1870-71, with what sounds like a return to the age of Terror. During the Paris Commune, priests were killed and churches desecrated, bourgeoisie and proletariat were bitter enemies, and the self-righteous republic behaved like a dictatorship. Defeat by Prussia and civil war in Paris “demoralised France as a nation and demonstrated the fragility of its national identity”.

The structure of the book entails a certain amount of repetition - pre- and post-1870, with chapters in each part on politics, international affairs, religion, women and culture. But this gives a vivid sense of the extreme stickiness of French history. Some of Gildea's sub-headings are reminders that the “children of the revolution” struggled to escape from their bloody past: Rerunning the Revolution, Rerunning the Republic, Rerunning the Empire. For that matter, French politics today is still trying to shake off the legacy of the second world war. It was not until the early 20th century that there was “a coherent national consciousness and confidence”. All the little tribal communities that had crazed the nation and frustrated administrators finally came together in the muddy wastelands of northern France.

Gildea ends his account with the death of the writer Charles Péguy in the battle of the Marne. “He drew himself up,” said a witness, “defying the machine guns, as if inviting the death he had glorified in his poetry.” This “martyrdom” of a romantic nationalist provides what looks like a suitably symbolic conclusion. Péguy “was a republican, Dreyfusard and socialist but also a Catholic and attached to the values of old France”. The nation, in a sense, would prevail, at the cost of a 1.5m French citizens, which is almost exactly what Peter Cook's blimpish squadron leader had in mind: “We need a futile gesture at this stage. It will raise the whole tone of the war.”

Children of the Revolution is the second volume of the New Penguin History of France. Its Penguin predecessor, Alfred Cobban's A History of Modern France, is still an excellent introduction, but “history” is now a more capacious concept. Gildea, who is professor of modern history at Oxford, was a student of Theodore Zeldin and shares his master's appetite for social and cultural evidence. This is not just a history of Parisian politics. Although it bulges with certifiable fact, it also gives a face to many neglected individuals and makes wonderful use of fictional characters (especially Balzac's) to provide one of the most dependable and readable accounts of the nation that almost never was.

Children of the Revolution by Robert Gildea
Allen Lane £30 pp560 Buy the book from Books First £27.00 including free delivery

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