John Matthews has made a lifetime study of every aspect of the Arthurian legends, from their origins to modern retellings. He has published more than 100 titles on myth, folklore, and ancient traditions, and he won a BAFTA for his work on the movie King Arthur (2004). Among his many authored and coauthored titles are The Book of Merlin, The Complete King Arthur, and The Lost Book of the Grail.

Maarten Haverkamp is a senior lecturer/researcher at The Hague University of Applied Sciences. An avid collector of rare medieval books for more than 20 years, his years of translation work and collaboration with John Matthews have culminated in the completion of the first English translation of a rare text nearly forgotten for more than 500 years.