Rebellio, among the Romans, was where those who had been formerly overcome in battle, and yielded to their subjection, made a second resistance: but with us it is generally used for the taking up of arms traiterously against the king, whether by natural subjects, or others when once subdued; and the word rebel is sometimes applied to him who wilfully breaks a law; also to a villein disobeying his lord.

There is a difference between enemies and rebels. Enemies are those who are out of the king's allegiance: therefore subjects of the king, either in open war, or rebellion, are not the king's enemies, but traitors. And David prince of Wales, who levied war against Edw. I. because he was within the allegiance of the king, had sentence pronounced against him as a traitor and rebel. Private persons may arm themselves to suppress rebels, enemies, &c.