Rocky and the Armenian

In the age of Bradley Manning and girls in Vegas with cameraphones, it seems quaint that France should be getting its political gossip from the literary invention of 1641, the roman à clef. Le Monarque, son fils, son fief: Hauts-de-Seine – chronique d'un règlement des comptes by Marie-Célie Guillaume has stayed on the non-fiction (nobody's fooled) bestseller lists since it was published earlier in the summer and has sold thirty thousand copies in France. Not content with having caught Sarkozy leering at the Israeli model Bar Rafaeli, complaining to Obama about Netanyahu, getting pissed with Putin, stealing a pen from Romania's president and calling a group of journalists his 'amis pédophiles', France wants to read about their ex-president accepting blowjobs for subsidies, stabbing political allies in the back and giving his son one of the most powerful positions in his old fiefdom.

The roman à clef came out of the literary salons of 17th-century Paris. Madeleine de Scudéry gained her introduction to the Marquise de Rambouillet's salon in 1641, where she met Corneille, La Fontaine and Madame de Sevigné, and began work on a novel that would run to ten volumes and more than two million words, Artamène or Cyrus the Great. A fashionable heroic novel set in ancient Persia, it was also understood to incorporate pen portraits of the salonniers under different names; a key was printed so nobody could miss the fact that 'Cyrus the Great' was also Le Grand Condé. It came out in 1649 and was reprinted in 1650, 1653, 1654 and 1656. From 1657, Scudéry's ownsamedi on rue de Beauce brought visiting royalty such as Christina, Queen of Sweden together with academicians, grammarians, Louis XIV's advisers, as well as other women of letters such as the king's secret second wife, Madame de Maintenon. Another novel, Clélie, or Clef-ly, came out in 1654 and depicted Louis XIV, among others, in its story of love lost and found in Tarquin's Rome. It became the bestselling book of the century. The pattern was set: romans à clefs should be written by posh insiders with a democratic impulse to let the world see power as it is really is; the settings and names, playful but transparent, should have an air of antiquity. And they should be bestsellers.

Guillaume's 'livre assassine' fits the pattern. She is the daughter of a baron, niece of Chirac's justice minister and a descendant of Napoléon Bonaparte's brother-in-law. She was chief of staff for Patrick Devedjian, the député for Hauts-de-Seine and an old ally of Sarkozy's. Hauts-de-Seine, the second richest department in France, was where Sarkozy started his political career and where he built his stronghold. Sarkozy hung on to posts as the département's president and mayor of Neuilly while serving as finance and then interior minister under Chirac.

The novel begins just after Sarkozy's 2007 election win in the Vieux Pays (France). Monarque or Rocky (Sarkozy) summons his old friend L'Arménien (Devedjian) to the Château (the Elysée Palace) to inform him that he can't give him the Sceau régalien (the Garde des Sceaux, the Keeper of the Seals a.k.a. the Justice Ministry) as promised, because 'I am not a party man – I'm the Monarch now, the nation's man . . . I want my government to be open, to show that I can bring people together no matter their party.' When Devedjian was given the post of president of Hauts-de-Seine (la Principauté) in 2007, and the Justice Ministry went to Rachida Dati (Belle-Amie) instead, he told the papers, including Le Figaro (La Pravda), that he was 'in favour of a government open to a wide range of people – even Sarkozyists'. When she hears the news, Baronne (Guillaume) is furious that her boss – 'a coiner of killer lines and a tireless swashbuckler' – has been overlooked: 'But she's nothing but a little courtesan!' Rocky, meanwhile, is already on the phone to the Tsar (Putin) about their bear-hunting trip.

The courtesans, the royalty, the stilted wit: it all hints at the pre-Revolutionary France that inspired the first romans à clefs. Like those it is also an inquiry into contemporary political conduct: Guillaume, ickily on the side of her swashbuckling boss, is asking whether France wants a president who believes that principles 'are only for people who lack imagination' or someone of the 'old style, who believes in friendship and keeping promises'.

When the book came out on 14 June, Guillaume still worked for Sarkozy's party, but the book's success forced Devedjian, who for years had resisted Sarkozy's requests for her head, to fire her. He has said that Le Monarque, son fils, son fief 'is a woman's book, describing an environment created by reptilian-minded men with a great deal of natural brutality'. And the best sort of environment for a novelist, especially the sort who's just writing down what you say. Guillaume's novel, as UMP party loyalists realised, is un éloge à la normalité. But the roman à clef may not be entirely dead under Hollande: there are at least three novels about Dominique Strauss-Kahn and two books about Valérie Trierweiler coming out this rentrée littéraire.