[437] Thus Hall, § 32.
Notification of Occupation to other Powers.
§ 224. No rule of the Law of Nations exists which makes notification of occupation to other Powers a necessary condition of its validity. But as regards all future occupations on the African coast the Powers assembled at the Berlin Congo Conference in 1884-1885 have by article 34 of the General Act[438] of this Conference stipulated that occupation shall be notified to one another, so that such notification is now a condition of the validity of certain occupations in Africa. And there is no doubt that in time this rule will either by custom or by treaty be extended from occupations on the African coast to occupations everywhere else.
[438] See Martens, N.R.G. 2nd Ser. X. p. 426.
Extent of Occupation.
§ 225. Since an occupation is valid only if effective, it is obvious that the extent of an occupation ought only to reach over so much territory as is effectively occupied. In practice, however, the interested States have neither in the past nor in the present acted in conformity with such a rule; on the contrary, they have always tried to attribute to their occupation a much wider area. Thus it has been maintained that an effective occupation of the land at the mouth of a river is sufficient to bring under the sovereignty of the occupying State the whole territory through which such river and its tributaries run up to the very crest of the watershed.[439] Again, it has been maintained that, when a coast line has been effectively occupied, the extent of the occupation reaches up to the watershed of all such rivers as empty into the coast line.[440] And it has, thirdly, been asserted that effective occupation of a territory extends the sovereignty of the possessor also over neighbouring territories as far as it is necessary for the integrity, security, and defence of the really occupied land.[441] But all these and other fanciful assertions have no basis to rest upon. In truth, no general rule can be laid down beyond the above, that occupation reaches as far as it is effective. How far it is effective is a question of the special case. It is obvious that when the agent of a State takes possession of a territory and makes a settlement on a certain spot of it, he intends thereby to acquire a vast area by his occupation. Everything depends, therefore, upon the fact how far around the settlement or settlements the established responsible authority that governs the territory in the name of the possessor succeeds in gradually extending the established sovereignty. The payment of a tribute on the part of tribes settled far away, the fact that flying columns of the military or the police sweep, when necessary, remote spots, and many other facts, can show how far round the settlements the possessor is really able to assert the established authority. But it will always be difficult to mark exactly in this way the boundary of an effective occupation, since naturally the tendency prevails to extend the sway constantly and gradually over a wider area. It is, therefore, a well-known fact that disputes concerning the boundaries of occupations can only rarely be decided on the basis of strict law; they must nearly always be compromised, whether by a treaty or by arbitration.[442]
[439] Claim of the United States in the Oregon Boundary dispute (1827) with Great Britain. See Twiss, I. §§ 126 and 127, and his "The Oregon Question Examined" (1846); Phillimore, I. § 250; Hall, § 34.
[440] Claim of the United States in their dispute with Spain concerning the boundary of Louisiana (1803), approved of by Twiss, I. § 125.
[441] This is the so-called "right of contiguity," approved of by Twiss, I. §§ 124 and 131.
[442] The Institute of International Law, in 1887, at its meeting in Lausanne, adopted a "Projet de déclaration internationale relatif aux occupations de territoires," comprising ten articles; see Annuaire, X. p. 201.