4
You didn't show us a map, but the Central Powers that joined together in World War I were these four countries:
GermanyAustria-HungaryThe Ottoman Empire Bulgaria
This group was also known as the Quadruple Alliance. Â
Further context/detail:
In the years prior to World War I, there was much military buildup and alliance formation happening among the nations of Europe. Â This all served to increase tensions between the nations of Europe. Â There was pressure to form alliances with other nations to strengthen a nation's defenses in case there was a war. Â The Triple Entente and the Triple Alliance set up in opposition to each other. Â The Triple Entente consisted of Britain, France and Russia. Â The Triple Alliance consisted of Germany, Austria-Hungary, and Italy. Â When the war broke out, Italy shifted its loyalties and sided with the Allies (Britain, France, Russia). Â Germany and Austria-Hungary picked up Bulgaria and the Ottoman Empire as additional allies during the war, known as the Central Powers.