During the French Revolution, radicalism emerged as a prevalent force shaping the trajectory of events from 1789 to 1799. Rooted in the desire for profound societal change, radicalism in this context refers to the extreme measures adopted by revolutionaries to achieve their objectives, which included the comprehensive transformation of political, social, and economic structures. The rise of radicalism became evident with the influence of the Jacobins, a political club that advocated for republicanism and centralized government. Under the leadership of figures such as Maximilien Robespierre and Georges Danton, the Jacobin Club pushed for measures that would later become hallmarks of radical revolutionary policy. One such policy was the Reign of Terror (5 September 1793 – 28 July 1794), during which the Committee of Public Safety (led by Robespierre) exercised authoritarian control and executed thousands of perceived enemies of the revolution. The primary aim was to eliminate counter-revolutionary threats and solidify the new republican order. Radicalism also manifested in the economic sphere through initiatives like the Law of the Maximum, which aimed to control the prices of essential goods. This law, enacted on 29 September 1793, was intended to curb inflation and ensure that basic necessities remained accessible to the common populace. However, it also led to a black market and further economic instability. Cultural radicalism was promoted through the establishment of the Cult of the Supreme Being (8 June 1794) and the dechristianization movement. These efforts sought to replace traditional religious and cultural institutions with revolutionary ideals. For example, the French Republican Calendar was introduced to break away from the Christian Gregorian calendar and reflect revolutionary secular values. Moreover, the radical restructuring of French society included the abolition of feudal privileges and seigneurial rights (4 August 1789), representing a significant departure from the ancien régime. This was followed by the National Convention's decree on the abolition of the monarchy and the establishment of the French Republic on 21 September 1792. These radical changes dismantled the long-standing social hierarchy and paved the way for new societal norms. Radicalism also informed military strategies, evident in the levée en masse (23 August 1793), a policy of mass conscription that mobilized the entire nation for war. This strategy was essential in repelling the external threats posed by coalition forces opposed to the revolution. The period of radicalism eventually waned following the fall of Robespierre on 27 July 1794 (9 Thermidor Year II), marking the end of the Reign of Terror and signaling a shift towards more moderate policies. Nevertheless, the radical phase profoundly influenced the subsequent direction of the revolution, leaving a lasting legacy on French political and social life.