The documents published in these volumes were selected with a view to presenting a comprehensive record of the diplomatic relations between the United States and Japan in regard to matters related to the causes of conflict between the two countries from the beginning of the Japanese occupation of Manchuria on September 18, 1931, to the Japanese surprise attack on Pearl Harbor on December 7, 1941, and the declaration of war by the United States on December 8, 1941.

The amount of background material here printed has been limited by the necessity of keeping the publication within a reasonable compass. It was obviously impossible to include an absolutely complete selection of even the more important of the pertinent reports coming to the Department from American diplomatic representatives and other observers during the ten years covered. Therefore only reports of special significance have been selected.

While the American Government consulted with other interested powers and at times took parallel action in dealing with crises arising in the Far East during this period, it was not its practice to take joint action. It has therefore been thought advisable to limit the selection to those documents relating directly to American-Japanese relations without entering into the ramifications of discussions with third powers.

The correspondence with the Japanese Government with respect to losses by American nationals due to bombings and other acts of the Japanese armed forces in China is so voluminous that documents in record of representations in many individual cases have been omitted. This printed record therefore includes only the record of representations of a general character and a number of notes on particular incidents which were thought to be typical.

It is contemplated that additional documents relative to some of the developments treated in the present publication and to other phases of the policy of the United States toward the Far East during the years 1931–1941 will be published in the regular annual volumes of Foreign Relations of the United States.