In the mid 1930s, most of the international community did not think Adolf Hitler’s Germany would start the next great war. Indeed, many thought that it could be a bulwark against communism. Although fears of communist invasion had abated somewhat following the ascension of Joseph Stalin who helped to normalize the nation in international relations through trade with capitalist countries, the Soviet Union was still a specter hanging over Europe and the world. Thus, Fascist leaders throughout the world used anti-communist rhetoric to increase their public image. The culmination of this effort was the Anti-Comintern pact, signed first in 1936 by Germany and Japan.
The impetus for the negotiations between Japan and Germany that led to the pact was the Soviet rapprochement with moderate and liberal parties in Western nations. In the 1920s and into the early 1930s the Soviet policy was that social democrats, liberals, and fascists were all aligned and used the term “social fascists” to attack moderates. In Germany, the Communist party’s refusal to work with non-communist anti-fascist parties allowed Hitler to rise to power. Stalin believed that the continuation of the hostile-to-all policy could allow Fascists to gain power in other countries and so at the Seventh World Congress of the Comintern he ordered Communist parties to work with moderates against Fascists. Seeing the union of the center and the left against their ideology, Nazi leaders looked to form a united Fascist front and so began negotiations with Imperial Japan to form an anti-Communist alliance which they could use to rally international support. While the negotiations were disordered and the USSR did learn of them through subterfuge, Germany and Japan were able to agree to a defensive pact. Further, a secret portion of the agreement called for a united anti-Soviet foreign policy. The pact would expand in 1937 with Italy signing on followed by Spain, Hungary, and Japan’s Manchurian puppet in 1939. However, the relevance of the pact decreased following the Molotov-Ribbentrop Pact that resulted in improved German-Soviet relations. Japan became more anti-American after it and the USSR signed a non-aggression pact following a border conflict. Nevertheless, the two nations would renew it in 1941 and in that year a number of Axis-occupied and allied nations would join. Because the German invasion of the USSR was offensive Japan was not obligated to join and so it remained at peace with the Soviet Union until 1945. The fall of Nazi Germany and the defeat of Imperial Japan formally ended the pact; any relevance it had ever had ceased to exist years earlier.
The Anti-Comintern Pact is an example of pure diplomatic posturing. There was never any real ideological unit between Germany and Japan, and both nations would betray its word or its principle when it suited them. Fascism is an ideology that is nationalistic to an extreme degree, and fascist dictators tend to only make decisions that they think will benefit their nation even at the expense of their nominal allies. The lack of cooperation between the Axis powers contrasts with the cooperation between the Western Allies and the Soviet Union, and was a major factor in the Allied victory.