The Historia Francorum is the most important contemporary source for the Merovingian age. It is written in ten books, of which one to four recount the world's history from the Creation and move on to the Christianization of Gaul, the life and times of Saint Martin of Tours, the conversion of the Franks, the conquest of Gaul under Clovis, and the history of the Frankish kings down to the death of Sigebert I in 575. From the fifth book on, Gregory starts the second part of the book, on his contemporary history, closing Book 6 with Chilperic I's death in 584. The third part, from books 7 to 10, take the account to the year 591, and concludes with a plea for further chroniclers to preserve his work in entirety. An epilogue was written in 594, the year of Gregory's death.