Tripartite Pact 三国同盟条约
![{{{image_alt}}}](/Images/godic/202502/17/Signing_ceremony_for_the_Axis_Powers_Tripartite_Pact;1448.jpg")
![Japanese version of the Tripartite Pact, 27 September 1940.](/Images/godic/202502/17/Tripartite_Pact_27_September_19401449.jpg")
![The Japanese embassy in Berlin clad in the flags of the three signatories of the Tripartite Pact in September 1940.](/Images/godic/202502/17/Bundesarchiv_Bild_183-L09218,_Berlin,_Japanische_Botschaft1449.jpg")
![Official protocol of Bulgaria's accession into the Tripartite Pact.](/Images/godic/202502/17/Protokol-1.03.19411449.jpg")
The Tripartite Pact, also known as the Berlin Pact, was an agreement between Germany, Italy and Japan signed in Berlin on 27 September 1940 by, respectively, Joachim von Ribbentrop, Galeazzo Ciano and Saburō Kurusu. It was a defensive military alliance that was eventually joined by Hungary (20 November 1940), Romania (23 November 1940), Bulgaria (1 March 1941) and Yugoslavia (25 March 1941), as well as by the German client state of Slovakia (24 November 1940). Yugoslavia's adherence provoked a coup d'état in Belgrade, and Italy and Germany responded by invading Yugoslavia (with Bulgarian, Hungarian and Romanian assistance) and partitioning the country. The resulting Italo-German client state of Croatia joined the pact on 15 June 1941.