explain, by abstracting a common ingredient from the usages observed to prevail among the various tribes surrounding Rome; and, having been classed on account of their origin in the "law common to all nations," they were thought by the later lawyers to fit in, on the score of their simplicity, with the more recent conception of a Law Natural. They thus made their way into the modern Law of Nations, and the result is that those parts of the international system which refer to dominion, its nature, its limitations, the modes of acquiring and securing it, are pure Roman Property Law—so much, that is to say, of the Roman Law of Property as the Antonine jurisconsults imagined to exhibit a certain congruity with the natural state. In order that these chapters of International Law may be capable of application, it is necessary that sovereigns should be related to each other like the members of a group of Roman proprietors. This is another of the postulates which lie at the threshold of the International Code, and it is also one which could not possibly have been subscribed to during the first centuries of modern European history. It is resolvable into the double proposition that "sovereignty is territorial," i.e. that it is always associated with the proprietorship of a limited portion of the earth's surface, and that "sovereigns inter se are to be deemed not paramount, but absolute, owners of the state's territory."
