François Claudius Ravachol (French: [ʁavaʃɔl]; born Koenigstein; 14 October 1859 – 11 July 1892) was a French illegalist anarchist mainly known for his terrorist activism, impact, the myths developed around his figure and his influence on the anarchist movement in France.

Born in 1859 in Saint-Chamond, in the Saint-Étienne area, Ravachol grew up in poverty and domestic violence. Later, he began a life of crime marked by the murder and robbery of a rich hermit. In this city, Ravachol gradually adopted anarchist ideas and met other activists, such as Rosalie Soubère and Joseph Jas-Béala. He managed to escape from arrest, and with these two accomplices, the militant moved to Paris in 1891. There, joined by the young anarchist militant Charles Simon and maybe Gustave Mathieu, they carried out the Saint-Germain and Clichy bombings, targeting the judge and prosecutor responsible for the judicial persecution of anarchists arrested during the Clichy affair (1891).

Quickly arrested after the second attack, he stood trial, took full responsibility for the bombings in an effort to protect his companions, and was sentenced to life imprisonment with mitigating circumstances granted by the jury. Later, he was tried for the hermit’s murder and condemned to death, ultimately being guillotined on 11 July 1892, at Montbrison.

Although he was swiftly captured, arrested, and executed shortly after his attacks, which caused no fatalities, Ravachol is widely regarded as one of the launchers of the Ère des attentats (1892–1894). His assumption of full responsibility, efforts to exonerate his companions, and transformation from criminal to 'people’s avenger' in a sense, made him a martyr for anarchists and created the myth and folk hero of Ravachol within the French population. He also became the cultural archetype of the 'anarchist terrorist'. Ravachol's actions also marked a turning point in the evolution of terrorism; he was one of the first terrorists to move away from a symbolism centered on individuals and toward one centered on locations, targeting a place as much as a person, in his case. This aspect has become important in modern terrorism but was little understood by the contemporary press, which failed to grasp the motivations behind his actions.

François Claudius Ravachol was born 14 October 1859 in Saint-Chamond, Loire. He was the eldest child of the four children of a Dutch father (Jean Adam Koenigstein) and a French mother (Marie Ravachol). His father beat his mother and eventually abandoned the family, leaving Marie Ravachol and their children alone. For her part, she worked, whenever she had the opportunity, as a laborer in a raw silk industry. His mother frequently sent him to beg for money for the family and he started working at a very young age, even though he was attending school.

He left school at the age of eleven, after being bullied by his classmates because he wore "shabby" clothes. Around this time, he worked as a livestock herder during the winter, doing so without proper shoes, which caused his feet to be constantly frozen. His younger sister died of fever around this period. In the following years, Ravachol worked as a shepherd but also as a miner and in various other industries in the region. He was once fired from a job for arriving five minutes late, despite having worked many unpaid overtime hours. Around the age of 16, he secured a position in Saint-Chamond as an apprentice dyer with Richard and Puteau. However, this apprenticeship ended without the dyers deciding to keep him on or teach him more about their craft in greater detail. For additional income he played accordion at society balls on Sundays at Saint-Étienne for 5 francs per evening.

When he completed his apprenticeship without success, Ravachol left Saint-Chamond and the Saint-Étienne region to go to Lyon in search of work. There, he began attending public readings in study circles that read socialist and anarchist newspapers. At the age of 18, Ravachol read the book The Wandering Jew (1844) by Eugène Sue, which, according to his own testimony, started his distanciation from religious ideas. After a lecture given by the communard Paule Minck, in which she discussed the Semaine sanglante (Bloody Week), on 3 December 1881, in Saint-Chamond, he fully completed his break from religion.

After being dismissed from a new job along with his brother, he found himself unemployed and in poverty. Unable to provide for his family, Ravachol began by stealing chickens, while his brother stole coal. At the same time, he gradually became an anarchist and started attempting to make bombs, though without success at first. He was already in possession of dangerous materials, as he was arrested after supplying sulfuric acid to a woman.