In The Crime of Napoleon, Claude Ribbe accuses the emperor of genocide, gassing rebellious blacks more than a century before the Nazis' extermination of the Jews.

His accusations refer to the extreme methods used to put down a ferocious uprising in Haiti at the start of the 19th century. Then known as San Domingo, the colony was considered a jewel of the French empire and to save it troops launched a campaign to kill all blacks aged over 12.

"In simple terms, Napoleon ordered the killing of as many blacks as possible in Haiti and Guadeloupe to be replaced by new, docile slaves from Africa," Ribbe said yesterday.

He said he had found accounts from officers who refused to take part in the massacres, especially the use of sulphur dioxide to kill slaves held in ships' holds.

His book is already provoking controversy prior to its publication on Thursday. The newspaper France Soir juxtaposed images of Napoleon and Hitler yesterday before asking: "Did Napoleon invent the Final Solution?"

But in an editorial, it condemned the "inanity" of Ribbe's argument. Ribbe, 51, who is of French-Guadeloupe extraction, said he was unrepentant.

"I want the French to know exactly what happened in that period," he said. "As for the good things Napoleon did, that is irrelevant. Hitler developed the autobahns and inspired the Volkswagen; are we supposed to excuse him for his war crimes?"

Ribbe, who was recently appointed a human rights commissioner by the prime minister, Dominique de Villepin, added: "I was taught to think of Napoleon as a superstar. To mention his crimes against humanity has been a taboo."

Peter Bouzer