Christopher Gravett is a former Senior Curator at the Royal Armouries, Tower of London, and is a recognised authority on the arms, armour and warfare of the medieval world. He has worked as an advisor for numerous TV and film productions, and for Osprey has previously written Warrior 1: Norman Knight 950-1204 AD, Campaign 13: Hastings 1066, and two Fortress volumes on Norman Stone Castles, among others. He currently works as senior curator at Woburn Abbey in Bedfordshire. Adam Hook studied graphic design, and began his work as an illustrator in 1983. He specializes in detailed historical reconstructions, and has illustrated Osprey titles on the Aztecs, the Greeks, several 19th century American subjects, and a number of books in the Fortress series. His work features in exhibitions and publications throughout the world.