Which country was not in the Triple Alliance?

The Triple Alliance was an agreement between Germany, Austria-Hungary, and Italy. It was formed on 20 May 1882 and renewed periodically until it expired in 1915 during World War I. Germany and Austria-Hungary had been closely allied since 1879. Italy was looking for support against France shortly after it lost North African ambitions to the French. Each member promised mutual support in the event of an attack by any other great power. The treaty provided that Germany and Austria-Hungary were to assist Italy if it was attacked by France without provocation. In turn, Italy would assist Germany if attacked by France. In the event of a war between Austria-Hungary and Russia, Italy promised to remain neutral. The existence and membership of the treaty were well known, but its exact provisions were kept secret until 1919.

When the treaty was renewed in February 1887, Italy gained an empty promise of German support of Italian colonial ambitions in North Africa. Austria-Hungary had to be pressured by Otto von Bismarck into accepting the principles of consultation and mutual agreement with Italy on any territorial changes initiated in the Balkans or on the coasts and islands of the Adriatic and Aegean seas. Italy and Austria-Hungary did not overcome their basic conflict of interest in that region despite the treaty. In 1891 attempts were made to join Britain to the Triplice, which, though unsuccessful, were widely believed to have succeeded in Russian diplomatic circles.