Depending on what you read, Maximilien de Robespierre was a defender of the poor and downtrodden -- "the Incorruptible" who defended the values of the French Revolution to the end.
Or he was a monster who slaughtered thousands for revolutionary crimes, a lawyer who opened up the path of legalised terror later trod by Hitler and Stalin.
Now, with the help of 21st-century tools, forensic scientists are providing insights into a figure who left such a deep but contested imprint on history.
Robespierre, they say, probably suffered from a crippling auto-immune disorder called sarcoidosis -- a disease that may have played an indirect role in his downfall.
In 1794, the ultra-radical would have been severely weakened when his terrified foes mustered the courage to rush him to the guillotine, they say.
"He was killed by the guillotine but he was already exhausted by the political battle, his insomnia and his own frenetic personality," said Philippe Charlier, one of Europe's leading forensic anthropologists.
"But he was also weakened by this disease, which debilitates and tires the body," Charlier said in a phone interview with AFP.
In sarcoidosis, the immune system goes haywire and attacks the body's own tissues. Its signature is patches of reddened, swollen tissue called granulomas, but the inflammation also causes knock-on problems in organ functions.
Charlier, of the University of Versailles, and Philippe Froesch of the Parc Audiovisual de Catalunya in Barcelona, write up their conclusions in a letter to The Lancet medical journal, published on Friday.
Death mask clue
They build the diagnosis on a reconstruction of Robespierre's face, contemporary portraits, a death mask made by Madame Tussaud -- now known for the famous waxworks museum in London -- and eyewitness accounts.
The list of known symptoms is long: vision difficulties; nose bleeds so extreme "he covered his pillow with fresh blood each night"; yellow skin, a sign of jaundice; suppurating leg ulcers; and permanent twitching of the eyes and mouth.
He also had frequent outbreaks of skin disease, in addition to deep facial scars that resulted from smallpox.
"The retrospective diagnosis that includes all these symptoms is diffuse sarcoidosis," extending to the upper respiratory tract, the eyes and either the liver or pancreas, they write.
"The disease worsened between 1790 and 1794."
In the early stages of the 1789 French Revolution, Robespierre, inspired by the writings of Jean-Jacques Rousseau, carved out a reputation as a defender of universal human rights and the "sans-culottes," France's under-class.
As France descended into paranoia, fuelled by suspicions among the Revolutionaries of plots to restore the monarchy, Robespierre became more more and more powerful.
The turning point came in 1793, when deputies passed laws authorising the revolutionary government to suspend peacetime legal safeguards against the use of coercion and violence.
It was the start of "La Terreur," the first known time in history that terror became enshrined as a legal tool to achieve a higher political goal.
Robespierre played a key role in framing the law and in the bloodbath that followed. More than 16,000 people around France were guillotined after trials that were often little more than a legal figleaf.
As many as several hundred thousand more, according to some estimates, died in in summary killings or in atrocities, particularly in the royalist Vendee region.
During this time, Robespierre started to pick off his rivals one by one.
But after a four-week absence from the Paris political scene in which, sick and depressed, he never left his home, his surviving enemies rallied against him and his followers.
He was beheaded on July 28, 1794, at the age of 36, suffering a pistol wound to the jaw -- either self-inflicted or fired by a gendarme during his arrest the night before -- that left him tortured and grotesque-looking, according to contemporary accounts.
The cheers resounded around the Place de la Revolution -- the Place de la Concorde today -- as his head was shown to the public, and the Terreur ended.
Historians have long differed over Robespierre's place.
Some say he was a scapegoat for the Terreur and should be honoured for his principles and incorruptibility. Others revile him as a tyrant who stained the Revolution's ideals with blood.
In 2011, a bid by Communist councillors in Paris to name a street after Robespierre was vetoed by the city's Socialist-led majority.
[Image via Agence France-Presse]