"L'Origine du Monde" (The Origin of the World), an 1866 oil painting by the realist painter Gustave Courbet, may hang on the walls of the Musee d'Orsay in Paris.
But its status as a cherished work of art did not stop Facebook shutting down the account of a French teacher who shared a picture of it, because of the social network's ban on nude images.
The teacher, Frederic Durand, accuses Facebook of deactivating his account "without warning or justification" in February 2011.
He promptly sued the company in the name of freedom of expression, but the case is coming to court only on Thursday after a years-long legal wrangle over jurisdiction.
Durand made repeated attempts to have his account restored but Facebook is not thought to have done so -- despite rule changes in 2015 clarifying that depictions of nudity in artwork were acceptable.
Nudity 'made sublime'
Durand had posted a link to an article exploring the history of the painting which used the famous image as a thumbnail.
His lawyer Stephane Cottineau acknowledged that Facebook banned nude content at the time, but he argued that the painting is "a major work" which is "part of France's cultural heritage".
The close-up of the woman's crotch and abdomen is a depiction of nudity that has been "glorified, made sublime, through the talent of the artist," Cottineau said.
The Musee d'Orsay, which has held the painting since 1995, says on its website that the work "escapes pornographic status" thanks to "Courbet's great virtuosity and the refinement of his amber colour scheme".
Facebook fought for five years to avoid being taken to court in France over the case.
It argued that the teacher, like all Facebook users, had signed off on terms and conditions that say any legal disputes must be settled in California, where the company is based.
But a Paris appeals court ruled in February 2016 that the case should be heard in France.
Facebook had in the meantime updated its policy in 2015 to clarify that photographs of paintings or sculptures depicting nudity were acceptable.
A Facebook search today returns numerous uncensored posts featuring images of "L'Origine du Monde".
The painting, one of several female nudes completed by Courbet, shocked the stiff bourgeois society of his time.
It is believed to have been commissioned by a Turkish diplomat in Paris who was forced to sell it after racking up huge debts because of his gambling addiction.