The purpose of this thesis is to examine the policies behind Soviet intervention in the Spanish Civil War. The U.S.S.R. had two principal foreign policy goals in the late 193O's, goals which were applied to Spain from the outset of the Civil War. These were to stop the spread of Fascism and to develop close relations with Britain and France. Both goals had as their foundation a concern for the security of the Soviet Union. Faced with the disappointment of France's policy of Non-Intervention, and at the same time by a worsening Republican military situation, the U.S.S.R. sought to pursue both goals with regard to Spain by conducting a holding action in the Iberian peninsula and simultaneously attempting to establish an effective Non-Intervention Committee. An effective Committee would, hopefully, promote good ties with the democracies and at the same time prevent the victory of Fascism in Spain. Until the Spring of 1937, Soviet policy in regard to Spain was conducted skillfully. In the first part of 1937, however, Stalin ordered a purge of the Catalan Left, which undermined his previous policy in Spain. Stalin's concern for his own personal power thus jeopardized a policy which had as its foundation the defense of the Soviet Union. / Master of Arts