Historians constantly wrestle with uncertainty, never more so than when attempting quantification, yet the field has given little attention to the nature of uncertainty and strategies for managing it. This volume proposes a powerful new approach to uncertainty in ancient history, drawing on techniques widely used in the social and natural sciences. It shows how probability-based techniques used to manage uncertainty about the future or the present can be applied to uncertainty about the past. A substantial introduction explains the use of probability to represent uncertainty. The chapters that follow showcase how the technique can offer leverage on a wide range of problems in ancient history, from the incidence of expropriation in the Classical Greek world to the money supply of the Roman empire.