The earliest documented source for a group ball game in Great Britain comes from Wales. "Historia Brittonum" "(The History of the Britons)", written in the ninth century, depicts events after the end of Roman rule and forms the basis of the Arthurian legend. The book is accredited to Welsh monk and historian Nennius who supposedly had access to 5th century sources which have not survived. The preface, which appears in several recensions credited to Nennius, is considered by some historians to be a later embellishment by an anonymous writer. Others believe "Historia Brittonum" to be a collection of stories from the 7th century. Regardless of erroneous historical content, the main text does demonstrate that group ball games were understood in the 9th century and that the author of chapter 41 believed these games were played by the Britons. The oldest surviving transcript dates to c.1100 A.D.