Lone wolf terrorism has a long and bloody past, even if the motivations and context of this tactic over the last three decades by right-wing extremists and, more recently, jihadi Islamists, have witnessed a noticeable spike with the onset of the Internet Age. By approaching lone wolf terrorism as a generic phenomenon, this article will retrace both the historical trajectory and recent revival of this self-directed recourse to the “terrorist cycle.” This extends to an overview of earlier waves of lone wolf terrorism (notably deriving from anarchist and leftist doctrines), as well as a survey of the surprisingly sparse academic literature on the subject in English. By way of contribution, this review of some key instances and interpretations of lone wolf terrorism pursues two straightforward aims. The first is the identification of a nearly 150-year tradition of lone wolf terrorism now at its most ideologically disparate and potentially destructive, and the second is a heuristic definition and accompanying discussion of pan-ideological, solo-activated terrorism.