During the twelfth and thirteenth centuries the crusaders constructed tens of castles across the Middle East, some merely small watchtowers, others massive strongholds or fortress cities - but why did the crusaders place so much importance on fortifications?

Nicholas Morton explores the development of this remarkable phenomenon asking key questions such as - how were they constructed? Where did the money come from and what techniques (whether from Eastern Christian or Muslim societies) influenced their design and creation?

About our speaker: Nicholas Morton is an associate professor in history at Nottingham Trent University. The author or editor of many books and articles, his most recent major publications are: The Crusader Storm: A Global history of the wars for the Middle East and The Mongol Storm: Making and Breaking Empires in the Medieval Near East.