My research is linked by an interest in how ancient coinage can contribute to our understanding of history. I am the author of Ancient History from Coins, which is currently available in six languages, and have written widely on Roman coinage and history.
My interests have ranged across many relevant spheres of history, including economic, monetary, political and cultural. My first book was a standard work on countermarks on Roman Provincial Coinage (then called ‘Greek Imperials’), using that data to explore the relationships between coinage and the army, the movement of people, inflation and the function of coinage. Since then I have written on why ancient states struck coins, on the supply and use of money in the Roman world, on coin circulation and the integration of the Roman economy, on coinage and identity in the Roman provinces, and on the process of monetisation of temperate Europe.
I have been heavily involved in initiatives to further the online presentation of numismatic data. I was the founding Director of Roman Provincial Coinage Online and, with Professor Andrew Wilson, of the Coin Hoards of the Roman Empire Project. I continue to direct both projects. I am also part of the team which developed Iron Age Coins in Britain and Celtic Coin Index Digital.
I act as an editor of the series Roman Imperial Coinage and Roman Provincial Coinage.
My current research is focussed on the Antonine coinage of Roman Egypt (AD 138–192) in preparation for volume 4 of the Roman Provincial Coinage series and on Roman hoards and hoarding.