The history of terrorism involves significant individuals, entities, and incidents associated with terrorism. Scholars often agree that terrorism is a disputed term, and very few of those who are labeled terrorists describe themselves as such. It is common for opponents in a violent conflict to describe the opposing side as terrorists or as practicing terrorism.

Revolutionary terror, also referred to as revolutionary terrorism or reign of terror, refers to the institutionalized application of force to counter-revolutionaries, particularly during the French Revolution from the years 1793 to 1795. The term "Communist terrorism" has also been used to describe the revolutionary terror, from the Red Terror in Russia and Cultural Revolution in China to the reign of the Khmer Rouge and others. In contrast, "reactionary terror", often called White Terrors, has been used to subdue revolutions.