Departing from Mario Turchetti's study on the concept of tyranny and tyrannicide, the author sets out to explore its specific use in the political discourse in the eighteenth century. Originally, as in the works of Plato and Montesquieu, tyranny was used in reference to degenerate forms of government. Tyranny and tyrannicide gained additional significance with its inclusion in the virulent discourse during the radicalization of the French Revolution. Based on the myth of Brutus and other classical sources, anti-tyrannical rhetoric in the form revolutionary literature and propaganda spurted political activism. As the figure of the king became the main obstacle to liberty and the foundation of a new republic, tyranny and tyrannicide became key concepts in the revolutionary movements.