United States. These laws will be unwritten international law, if nothing be adopted or announced to the contrary; or the express regulations of the government when it sees fit to make them. But in both cases it is the law of the United States for the time being, whether written or unwritten." 17

SECTION 6. TREATIES, DIPLOMATIC RELATIONS, ETC.

As one nation cannot by its own will create new principles of international law, so two states cannot do so by any agreement or treaty. Treaties or diplomatic correspondence, however, may be important as evidence of what the international law on the subject is, and may also establish precedents, which if followed by other countries, may ripen into law.

SECTION 7. INTERNATIONAL PUBLIC OPINION.

A source of international law which has recently become of importance is "international public opinion." In former times when the king was the state this source could of course be of no importance, but has developed with the growth of free governments. So recent has been its development that Davis is the first of prominent writers on the subject to mention it.

SECTION 8. WORKS OF TEXT WRITERS.

"The writings of those who have made the history and development of international usages a subject of special study will always constitute our chief source of knowledge upon the subject. The earlier writers were roughly grouped into two schools. One, made up chiefly of Continental authors, who were familiar with 17 Bradley J., in New York Life Ins.

Co. vs. Hendren, 92 U. S., 288.

the Roman law, and by whom great authority was attached to the views of text writers. The other, composed of English and American writers, whose works, strongly influenced by the common law of England, attach the greatest weight to the decisions of competent courts and to the precedents established by the usages of nations and recognized by them as binding in their intercourse with each other. The present tendency is to obliterate this distinction. The history of both the Roman and common law has been exhaustively studied, and is now generally known, and the historical method of treatment is found to be as successful in its application to international as to municipal law.

"A decided unanimity of opinion among authors as to the reason or justice of a particular usage is strong evidence of its general acceptance as a rule of international law. 'Writers on international law, however, cannot make the law. To be binding the law must have received the assent of the nations who are to be bound by it.' '' 18 19

18 Davis

on International Law,

pages 26-7.

19 For a convenient list of the pro

minent writers on this subject, see Wilson & Tucker on International Law, Sec. 13.

CHAPTER II.

HISTORY OF INTERNATIONAL LAW.

SECTION 9. HISTORY OF INTERNATIONAL LAW.

The close connection between history and law has already been referred to. Important, however, as a knowledge of history is throughout the whole course of his study, it is probably more essential to the student in the study of international law than in the study of any other branch of this science. With no superior authority to adopt principles of international law, such principles can only be the result of evolution, and the history of such evolution is the history of national relations.

SECTION 10. PERIODS OF THE HISTORY OF INTERNATIONAL LAW.

The history of international law falls naturally into four sharply defined periods. The ancient, the medieval, the modern, and the current. The first period begins with the dawn of history and terminates with the fall of the Western Roman Empire in 476. The second extends from the fall of the Western Roman Empire to the invasion of Italy by Charles VIII in 1494. The third period extends through the Crimean while the final period begins with the Declaration of Paris and continues down to the present day. Each of these periods has its own marked characteristics, which will be considered in the four succeeding sections.

war;

SECTION 11. INTERNATIONAL RELATIONS BETWEEN

ANCIENT NATIONS.

It is necessary to give to this section the title of international relations between ancient nations, for international law during this period was non-existent. The natural state between foreign nations was universally considered to be war. Peace could only exist as the result of express treaties. Nations were enemies or allies; there was, in theory, no middle ground.

The Greeks came the nearest among ancient nations to acquiring a conception of a system of international law; but their work along this line was limited in the scope of its applications to the inter-relations of the various Greek states. To the ancient Greek the inhabitants of the world were divided into Greeks and Barbarians, and however carefully the relations among the former might be regulated, nothing but mutual hostility and contempt was to be expected between the former and the latter.

The foreign policy of the Romans was through its whole period a most aggressive one. At the time of the highest development of the Roman Empire, Rome was surrounded on the north, south, and west by uncivilized or semi-civilized races, while their relation with the New Persian Empire on the east was one of almost unbroken hostility.

The development of any system of international law during a period of this character was an impossibility.

SECTION 12. INTERNATIONAL RELATIONS DURING THE MEDIEVAL HISTORICAL PERIOD.

The overthrow of the Western Roman Empire, in the fifth century, was the beginning of a new era in the

world's history. For the time it seemed like a retrogression. The civilization of the ancient world had been overthrown, and the new and higher civilization was far in the future. The central figure in the history of Western Europe during this period is the colossal institution of feudalism. The influence of feudalism was both towards, and away from, centralization. The sub-infeudation of the land was constantly tending towards the creation of new and minute powers, but the pryamiding feature of the system led to the growth of the theory that this should be continued one step higher; and that under the true organization of society there would be found a common world-wide superior sovereign, from whom the kings of the various countries would hold, as the vassals-in-chief in each country held from the king. The memory of the supremacy of the empire of Rome strengthened this view, as did also the claims of the Pope.

For a long period the center of the stage in European history is taken up with the contest between the Pope and the Emperor of the so-called Holy Roman Empire, for this position of supremacy. The long contest of the Guelfs and Ghibbelines, however, instead of establishing the supremacy of the leader of either faction, shattered the strength of both and resulted in the splitting up of a large portion of Western Europe into a vast number of minute states.

Medieval history, as generally written, is little more than an account of an endless series of military contests between the different European powers. One great advance, however, is to be noticed over the state of international relations in earlier times. Whatever the practice may be, it had at least come to be recognized in theory, and sometimes followed, that nations