The triple alliance of 1882 began when prussia

Military alliance

Explanation:

Triple Alliance, secret agreement between Germany, Austria-Hungary, and Italy formed in May 1882 and renewed periodically until World War I. Germany and Austria-Hungary had been closely allied since 1879. Italy sought their support against France shortly after losing North African ambitions to the French. The treaty provided that Germany and Austria-Hungary were to assist Italy if it were attacked by France without Italian provocation; Italy would assist Germany if Germany were attacked by France. In the event of a war between Austria-Hungary and Russia, Italy promised to remain neutral. This abstention would have the effect of freeing Austrian troops that would otherwise have been needed to guard the Austrian-Italian border.

When the treaty was renewed in February 1887, Italy gained an empty promise of German support of Italian colonial ambitions in North Africa in return for Italy's continued friendship. Austria-Hungary had to be pressured by German chancellor Otto Avon

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, the treaty notwithstanding. On November 1, 1902, five months after the Triple Alliance was renewed, Italy reached an understanding with France that each would remain neutral in the event of an attack on the other. Although the alliance was again renewed in 1907 and 1912, Italy entered World War I in May 1915 in opposition to Germany and Austria-Hungary.