The Tripartite Pact, also called the Three-Power Pact, Axis Pact, Three-way Pact or Tripartite Treaty was a pact signed in Berlin, Germany on September 27, 1940, which established the Axis Powers of World War II. The pact was signed by representatives of National Socialist Germany (Adolf Hitler), Italy (foreign minister Galeazzo Ciano) and Japan (ambassador Saburo Kurusu).
The Austro-Hungarian Empire had sided with Imperial Germany during World War I and had collapsed following the defeat by the Allies. Following the Treaty of Trianon, the Kingdom of Hungary was reduced greatly in size and this caused much resentment. To assuage this resentment, Germany and Italy implemented the Vienna Awards in 1938 and 1940 and this was subsequently followed by Hungary joining the Tripartite Pact on November 20, 1940. Collusion was further heightened when the Fascist Arrow Cross Party later came to power.
The Kingdom of Romania had joined the Allied Powers in World War I and had received Transylvania from Austro-Hungary. After Germany and Italy awarded parts of Transylvania back to Hungary and southern Dobruja back to Bulgaria and after the Soviet Union had taken Bessarabia, the Fascist Iron Guard party came to power and Romania joined the Tripartite Pact on November 23, 1940. This was partly due to the Romanian desire for protection against the Soviet Union.
On 14 March 1939, after the Munich Agreement, the Slovak Republic was formed from a portion of the dismembered Czechoslovakia. Hitler invited Monsignor Jozef Tiso to be the new nation's leader. Soon after it was formed, Slovakia was involved in a war with neighboring Hungary. Although Slovakia had signed a "Protection Treaty" with Germany, Germany refused to help Slovakia in direct violation of that treaty. The war resulted in territorial gains by Hungary at Slovakia's expense. Even so, Slovakia supported the German invasion of Poland. Slovakia joined the Tripartite Pact on November 24, 1940.
The Kingdom of Bulgaria had been on the losing side in World War I, losing territory to Serbia and Greece. During World War II, Germany needed military access through Bulgaria in order to attack Greece. Adolf Hitler promised the Bulgarian Tsar Boris III that Bulgaria would receive all the territory she had lost in return for Bulgaria joining the Axis. Boris agreed and prime-minister Bogdan Filov signed the Pact on March 1, 1941.
Kingdom of Yugoslavia
On March 25, 1941 in Vienna, Prince Paul (Pavle), Regent of the Kingdom of Yugoslavia, signed the Tripartite Pact. On March 27, the regime was overthrown by a military coup d'état with British support, and the 17 year old King Peter II of Yugoslavia seized power. General Dušan Simović became Peter's Prime Minister and the Kingdom of Yugoslavia initially tried to dissolve the Pact but later declared adherence to it.
The initial agreement of the document also regarded Yugoslavia's acceptance of the free movement of German troops around the country; this was unsatisfactory to the Führer, and resulted in the Invasion of Yugoslavia.
Postponing Operation Barbarossa, the Germans simultaneously attacked Yugoslavia and Greece. Starting on April 6, the German Air Force (Luftwaffe) bombed Belgrade for three days and nights. German ground troops (Wehrmacht Heer) moved in, and Yugoslavia capitulated on April 17.