Welsh mythology, the remnants of the mythology of the pre-Christian Britons, has come down to us in much altered form in medieval Welsh manuscripts such as the Red Book of Hergest, the White Book of Rhydderch, the Book of Aneirin and the Book of Taliesin. Other sources include the 9th century Latin historical compilation Historia Britonum (the History of the Britons) and Geoffrey of Monmouth's 12th century Latin chronicle Historia Regum Britanniae (the History of the Kings of Britain), as well as later folklore, such as The Welsh Fairy Book by W. Jenkyn Thomas [1908].