Here is a list of definite, possible and probable soures for King John:
- The Chronicles of England, Scotland and Ireland by Raphael Holinshed
- Actes and Monuments of Martyrs by John Foxe
- The Union of the Two Noble and Issustre Famelies of Lancastre and Yorke by Edward Hall
- The English Chronicle of Radulph of Coggeshall
- King John by John Bale
- The Troublesome Raigne of King John, Anonymous