The Yalta Agreement of February, 1945, was a major link in the structure of American policies in the Far East. It is a supplement to the Cairo Declaration which reaffirmed the principle of unconditional surrender of Japan and provided the basic outline of the postwar structure of power in the Far East. Insofar as the Yalta Agreement was designed to assure Soviet participation in the Pacific war, it was an expression of the policy of securing the unconditional surrender of Japan. Insofar as it was aimed at obtaining Soviet co-operation with the Nationalist government, it was an indispensable means to promote the American policy of peaceful unification of China. The immediate and primary considerations impelling American officials to conclude and implement it were undoubtedly military in nature. But their deeper thoughts centered on its political effects on the internal situation in China. Both the military considerations and political calculations reflected the powerful position of the Soviet Union in the Far East in the last year of the Pacific war and the inability of the United States to implement her policies without Soviet co-operation. The Yalta Agreement was the price paid for this co-operation.