John Acton was an English canon lawyer, known for his commentary on the writer on the ecclesiastical Constitutions of two papal legates of the thirteenth century. Sent to Henry III of England, they were Cardinal Otto, i.e. Oddone di Monferrato, and Cardinal Ottobone, i.e. Ottobuono de' Fieschi. His name is variously spelt Achedune, De Athona, Athone, and Eaton.