The satirical Le Roi des montagnes (1856; translated into English by Mary Louise Booth as The King of the Mountains,[4] and by Tom Taylor as The Brigand and His Banker, for a dramatized version)[5] is the best-known of his novels.
But his Tolla (1855), the story of a young Parisian actress, gave rise to charges of drawing too freely on an earlier Italian novel, Vittoria Savelli (1841).
The Lettres d'un bon jeune homme, written to the Figaro under the signature of "Valentin de Quevilly", provoked more animosities.
During the next few years, he wrote novels, stories, a play (which failed), a book-pamphlet on the Roman question, many pamphlets on other subjects of the day, innumerable newspaper articles, some art criticisms, rejoinders to the attacks of his enemies, and popular manuals of political economy, L'A B C du travailleur (1868), Le progrès (1864).
His more serious novels include Madelon (1863), L'Infâme (1867), the three that form the trilogy of the Vieille Roche (1866), and Le roman d'un brave homme (1880) – a kind of counterblast to the view of the French workman presented in Émile Zola's L'Assommoir.