When Emile is talking to his old friend Paul during dinner, he is wearing a pocket watch that is fastened to his vest button on the outside of the vest. But in the following cut when they are in the entertainment room, the pocket watch is now fastened to the button through the inside of the vest. It then changes back to the outside when he plays cards with his wife.
Zola is shown as not wanting to get involved in the Dreyfus Affair until he is won over by an emotional plea from Mme. Dreyfus following the Esterhazy trial. In fact, he had interested himself in the affair for some time before that and had written articles denouncing the anti-semitism that had condemned Dreyfus.
The young Zola is shown sharing a garret with Paul Cezanne. While they were friends, they did not live together in Paris. Also, they are shown as being friends long after Zola published the novel L'Oeuvre, whose main character is based on Cezanne. In fact, the book ended their friendship.
Nana is shown as the first novel Zola writes, and the first to have a popular success. In fact, Zola had written more than a dozen novels before Nana, many of which were successful.
Zola died in 1902. Dreyfus was not exonerated and reinstated into the Army until 1906. (In fact, after his return from Devil's Island, Dreyfus was tried again, convicted again and sentenced to 10 years in prison, but was pardoned in exchange for admitting guilt.)
The lettering on the door to Clemenceau's office at the newspaper misspells his first name "George" instead of the correct French spelling, "Georges".
When Nana comes into the café from the snow, the artificial snow stays on her clothes long after real snow would have melted, then suddenly in a second it disappears with the next cut.
At the beginning of the film, Zola is warned to stop "muckraking." This term did not come into use until about 40 years after the period shown in the film.
In this story set in France and featuring French characters, the written and printed texts are all in English.