Lukas de Blois is Emeritus Professor of Ancient History at Radboud University, Nijmegen, the Netherlands. He published books and articles on the history of the Roman Empire in the third century AD, the history of the Late Roman Republic, ancient historiography (Sallust, Tacitus, Cassius Dio), Plutarch's biographies and Greek Sicily in the fourth century BC. His most recent contribution is Image and Reality of Roman Imperial Power in the Third Century AD (Routledge, 2018).

R.J. van der Spek is Emeritus Professor of Ancient Mediterranean and West Asian History at the Vrije Universiteit, Amsterdam, the Netherlands. He specialises in the history of the ancient Near East in the context of Mediterranean history. He has published on Hellenistic Babylonia and economic history. He edited two volumes in the Routledge Explorations in Economic History on market performance (no. 68) and the history of monetary policy (no. 80) from ancient Mesopotamia to the modern world.