‘Treason’, said Maitland, ‘is a crime which has a vague circumference and more than one centre’. The law of treason which operated in England in the later middle ages had two major centres or elements, the Germanic and the Roman. This was also true of the treason laws of continental Europe, where the relative importance of the two components varied from state to state and even from province to province. The Germanic element was founded on the idea of betrayal or breach of trust [treubruch] by a man against his lord, while the Roman stemmed from the notion of maiestas, insult to those with public authority. Seditio is the word often associated in medieval writings with the Germanic concept, laesa maiestatis with the Roman. From the time of the collapse of the Roman Empire in the west in the fifth century, the Germanic idea of breach of trust was in retreat before the intellectually more advanced although partially conflicting notion of loss of majesty. As the invading peoples established primitive states they absorbed the atmosphere of Romanitas and their rulers assumed the dignities which they felt were suited to the successors of the Roman Emperors. To emulate Roman imperial style, as was often the aim, meant also to adopt in some degree the ideas of Roman law.

The laws of the Anglo-Saxons were affected by this process more slowly than those of most other Germanic peoples. What Roman influence there was may have been conveyed to England through the medium of the church.