The leading figure executed during the Reign of Terror in France was Georges Danton. A prominent revolutionary leader and advocate for the rights of the people, Danton was initially a supporter of the revolution and a key figure in establishing the First French Republic. However, as radical factions took control, he fell out of favor with the ruling committee led by Robespierre. In 1794, he was arrested and subsequently executed by guillotine. His death symbolized the intense political purges of the Reign of Terror and the extremes of revolutionary fervor during that period.