<P> Historians continue to debate the importance of the alliance system as one of the causes of World War I . At the start of World War I in 1914, all three Triple Entente members entered it as Allied Powers against the Central Powers: Germany and Austria - Hungary . </P> <P> However, the Triple Entente, unlike the Triple Alliance or the Franco - Russian Alliance, was not an alliance of mutual defense . Thus, Britain felt free to make its own foreign policy decisions in the 1914 July Crisis . </P> <P> Russia had previously been a member of the League of the Three Emperors, an alliance in 1873 with Austria - Hungary and Germany . The alliance was part of German Chancellor Otto von Bismarck ′ s plan to isolate France diplomatically; he feared that France's revanchist aspirations might make it to regain its losses in 1871 after the Franco - Prussian War . The alliance also served to fight against progressive sentiments, which the conservative rulers found unsettling, such as the First International . </P> <P> However, the League faced great difficulty with the growing tensions between Russia and Austria - Hungary, mainly over the Balkans, where the rise of nationalism and the continued decline of the Ottoman Empire made many former Ottoman provinces struggle for independence . </P>

Germany joined the triple alliance to protect itself against whom