Terrorism does not have a single, universal, definition. In its broadest sense, terrorism is the unlawful use of violence or intimidation backed by the credible threat of violence, especially against civilians, in order to advance political or ideological goals. Terrorism plagues the modern era, but it is not a modern phenomenon. Terrorists and terrorist groups have existed for centuries, going as far back as the days of the Roman Empire. Below are eighteen fascinating but lesser known facts about terrorist groups from the ancient and medieval worlds.
18. Terrorism Predates the Modern Era

Terrorist groups that relied on violence to intimidate societies and governments in order to achieve their aims have existed for millennia. History’s first clearly identifiable terrorists emerged in the Holy Lands in the first century AD. They grew out of a clandestine organization of fanatics who engaged in public murder and exemplary atrocities in a bid to gain freedom from a foreign occupier. A few centuries later during the medieval era, a movement of fanatical religious fundamentalists, again in the Middle East, declared that most of their co-religionists were backsliders, sinners, and apostates deserving of death. They engaged in a protracted campaign of terror, atrocities, and massacres, in much of the same territory where ISIS has operated in the twenty first century.