The belief in the superiority of one's own race, over all the other peoples of the world, is one which we find firmly imbedded in the minds of the inhabitants of all countries, both ancient and modern. This belief in the superiority of the race includes the belief in the great superiority of its laws, customs, and institutions. While this feeling is found with perhaps equal intensity among the nations of ancient and those of modern times, still the effect which it has had upon the people of the two periods has been strikingly different. In modern times its influence has taken the direction of developing the belief in what Kipling has denominated "the White man's burden," the tenet of which may be described as being a belief that it is the duty of those races possessed of higher laws to force them upon all so-called inferior races, either with or against their will, and that such races are sufficiently recompensed by the great gain from such laws and institutions, for any such minor losses they may incur, as the loss of their land or other property. The same underlying ideas had an almost diametrically opposite effect upon ancient races. In the eyes of all ancient nations their own laws and institutions possessed such peculiar and superior merit that no other race or people were worthy of them. Each race therefore jealously guarded its own laws to such a degree as to refuse to allow them to govern foreigners living in their very midst and under their jurisdiction. This principle of the racial rather than the territorial jurisdiction of laws, in fact, continued among many races almost down to the close of the middle ages.

The number of foreigners settled at Rome, for commercial or other purposes, made the question, as to the laws to govern litigation affecting resident foreigners, a most important one. This was recognized at an early period by the appointment of a new officer, the praetor peregrinus, to whom was assigned all cases between foreigners, or between a foreigner and a Roman, while suits between Roman citizens were left to the praetor urbanus. The praetor peregrinus was at once confronted with the question as to what system of laws to use to settle controversies which came before him. If both the litigants were citizens of the same country the laws of that country would be applied, but in the majority of these cases arising in cosmopolitan Rome, the suitors would be of different races.

Under these circumstances the idea of a jus gentium, or a general law of nations occurred to the praetors. The original theory upon which this system of laws was built was that there are certain rules and principles which are common to the laws of all countries, and that if these could be collected together and codified a system would result which could properly be applied in the settlement of disputes between citizens of any countries. Starting from this proposition the praetors set to work to develop the famous jus gentium. From the outset, however, the praetors were endeavoring to ascertain not what was common to the laws of other nations, but rather what was best among them, and to supplement any omissions in the system, by their own legislation. Many of the ablest lawyers of Rome seemed to have served as praetor peregrinus, and a system was soon developed which in all respects surpassed any of the contemporaneous systems of jurisprudence.

The jus gentium, as already stated, was created for the settlement of the controversies between foreigners, and was at first strictly limited to cases of this character. Gradually, however, the Roman citizens awoke to the fact that two systems of laws were being enforced in their territory, a superior and inferior one, and that they were carefully guarding the inferior system for themselves, and reserving the superior one for the despised foreigners. Shortly after this we find the distinctions between the two broken down, and the jus gentium furnishing the basis for a new and still greater system of Roman jurisprudence.