The substance of these lectures and discussions was put into form in August, 1919. During the period up to March 31, 1920, the manuscript was kept abreast of events in connection with the League and the Treaty of Versailles. As the purpose was to ana lyze the Covenant and Treaty at first hand and not to defend a thesis, or support policy with regard to any particular state, the failure of the United States to become an original member of the League has in no way disturbed the plan of the book. On N ovem ber 19, 1919, the United States Senate defeated ratification by a vote of 55 to 39, and again on March 19, 1920, by a vote of 49 to 35. On March 20, 1920, the Treaty of Versailles was returned to President Wilson. Whether or not the United States remains out side of the League, or becomes a member with reservations, the League Covenant is in force as to the present members; and, unless it fails utterly of its purposes, will affect the foreign relations of the United States both in the matter of peaceful cooperation and in settling disputes which might lead to a rupture. Moreover, the wisdom of the reservations proposed by the United States Senate can be appraised only by such a study as has here been attempted.