ASSUMPTIVE Arms, in Heraldry, are such as a Man has a right to assume of himself, in virtue of some Action. See ARMS.
As, if a Man who is no Gentleman of Blood, nor Coat Armour, takes a Gentleman, Lord, or Prince, Prisoner in any lawful War; he becomes entitled to bear the Shield of such Prisoner, and enjoy it to him and his Heirs.—The Foundation hereof is that Principle in Military Law, that the Dominion of Things taken in lawful War passes to the Conqueror.