The main function of the League of Nations were two- the maintenance of international peace and security and the promotion of international cooperation. According to the Preamble of the Covenant of the League of Nations, “The High Contracting parties, in order to promote international cooperation and to achieve international peace and security by the acceptance of obligation not to resort to war, by the prescription of open, just and honourable relations between nations, by the firm establishment of the understandings of international law as the actual rule of conduct among the governments, by the maintenance of Justice and a scrupulous respect for all treaty obligations in the dealings of organized peoples with one another, agree to this Covenant of the League of Nations”. The League wanted also to guarantee against aggression. Article 10 of the Covenant provided thus “The members of the League undertake to respect and preserve against external aggression the territorial integrity and existing political independence of all members of the League. In case of any such aggression or in case of any threat or danger of such aggression, the Council shall advise upon the means by which this obligation shall be fulfilled”. Provision was also made for open diplomacy. Article 18 provided that if any member of the League entered into any treaty or international engagement, it was required to get it registered, with the Secretariat of the League as soon as possible. If any treaty was not registered, the same was not binding.
Article 19 of the Covenant provided “The Assembly may from time to time advise the reconsideration by members of the League all treatises which have become inapplicable and the conditions whose continuance might endanger the peace of the world”. According to Oppenheim, “the principle reflected in article 19 was a modest beginning in an embryonic form of the legislative process in the society of nations”.
If there was a conflict between an obligation, under the Covenant and any other international obligation, the former was to enjoy priority. Article 23 provided thus “The members of the League severally agree that this Covenant is accepted as abrogating all obligations or understanding interse which are inconsistent with the terms thereof, and solemnly undertake that they will not hereafter enter into any engagement inconsistent with the terms thereof. In case any member of the League shall before becoming a member of the League, have undertaken any obligations inconsistent with the terms of this Covenant, it shall be the duty of such member to take immediate steps to procure its release from obligations”. Anyhow, an exception was made in the case of the Monroe Doctrine. Article 21 provided thus “Nothing in this Covenant shall be deemed to affect the validity of international engagements, such as treaties of arbitration of regional understanding like the Monroe Doctrine for securing the maintenance of peace”.