The Axis grew out of the diplomatic efforts of Germany, Italy, and Japan to secure their own specific expansionist interests in the mid-1930s. The first step was the treaty signed by Germany and Italy in October 1936. Benito Mussolini declared on 1 November that all other European countries would from then on rotate on the Rome–Berlin axis, thus creating the term "Axis". The almost simultaneous second step was the signing in November 1936 of the Anti-Comintern Pact, an anti-communist treaty between Germany and Japan. Italy joined the Pact in 1937. The "Rome–Berlin Axis" became a military alliance in 1939 under the so-called "Pact of Steel", with the Tripartite Pact of 1940 leading to the integration of the military aims of Germany, Italy and Japan.
At its zenith during World War II, the Axis presided over territories that occupied large parts of Europe, North Africa, and East Asia. There were no three-way summit meetings and cooperation and coordination was minimal, with a bit more between Germany and Italy. The war ended in 1945 with the defeat of the Axis powers and the dissolution of their alliance. As in the case of the Allies, membership of the Axis was fluid, with some nations switching sides or changing their degree of military involvement over the course of the war.
The term "axis" was first applied to the Italo-German relationship by the Italian prime minister Benito Mussolini in September 1923, when he wrote in the preface to Roberto Suster's Germania Repubblica that "there is no doubt that in this moment the axis of European history passes through Berlin" (non v'ha dubbio che in questo momento l'asse della storia europea passa per Berlino). At the time he was seeking an alliance with the Weimar Republic against Yugoslavia and France in the dispute over the Free State of Fiume.
The term was used by Hungary's prime minister Gyula Gömbös when advocating an alliance of Hungary with Germany and Italy in the early 1930s. Gömbös' efforts did affect the Italo-Hungarian Rome Protocols, but his sudden death in 1936 while negotiating with Germany in Munich and the arrival of Kálmán Darányi, his successor, ended Hungary's involvement in pursuing a trilateral axis. Contentious negotiations between the Italian foreign minister, Galeazzo Ciano, and the German ambassador, Ulrich von Hassell, resulted in a Nineteen-Point Protocol, signed by Ciano and his German counterpart, Konstantin von Neurath, in 1936. When Mussolini publicly announced the signing on 1 November, he proclaimed the creation of a Rome–Berlin axis.
Italy under Duce Benito Mussolini had pursued a strategic alliance of Italy with Germany against France since the early 1920s. Prior to becoming head of government in Italy as leader of the Italian Fascist movement, Mussolini had advocated alliance with recently defeated Germany after the Paris Peace Conference of 1919 settled World War I. He believed that Italy could expand its influence in Europe by allying with Germany against France. In early 1923, as a goodwill gesture to Germany, Italy secretly delivered weapons for the German Army, which had faced major disarmament under the provisions of the Treaty of Versailles.
In September 1923, Mussolini offered German Chancellor Gustav Stresemann a "common policy": he sought German military support against potential French military intervention over Italy's diplomatic dispute with Yugoslavia over Fiume, should an Italian seizure of Fiume result in war between Italy and Yugoslavia. The German ambassador to Italy in 1924 reported that Mussolini saw a nationalist Germany as an essential ally for Italy against France, and hoped to tap into the desire within the German army and the German political right for a war of revenge against France.