Reinsurance Treaty

The Reinsurance Treaty, (June 18, 1887), a secret agreement between Germany and Russia arranged by the German chancellor Otto von Bismarck after the German-Austrian-Russian Dreikaiserbund, or League of the Three Emperors, collapsed in 1887 because of competition between Austria-Hungary (Franz Joseph I) and Russia (Alexander III) for spheres of influence in the Balkans. The treaty provided that each party would remain neutral if the other became involved in a war with a third great power, though this would not apply if Germany attacked France or if Russia attacked Austria. Bismarck showed the Russian ambassador the text of the German-Austrian alliance of 1879 to drive home the last point. Germany paid for Russian friendship by agreeing to the Russian sphere of influence in Bulgaria and Eastern Rumelia (now part of southern Bulgaria) and by agreeing to support Russian action to keep the Black Sea as its own preserve. When the treaty was not renewed in 1890, a Franco-Russian alliance rapidly began to take shape.

Facing the competition between Russia and Austria–Hungary on the Balkans, Bismarck felt that this agreement was essential to prevent a Russian convergence toward France and to continue the diplomatic isolation of the French so ensuring German security against a threatening two-front war. He thereby hazarded the expansion of the Russian sphere of influence toward the Mediterranean and diplomatic tensions with Vienna.

The secret treaty signed by Bismarck and the Russian Foreign Minister Nikolay Girs was split in two parts:

As part of Bismarck's system of "periphery diversion" the treaty was highly dependent on his personal reputation. After the dismissal of Bismarck, his successor Leo von Caprivi felt unable to obtain success in keeping this policy, while the German Foreign Office under Friedrich von Holstein had already prepared a renunciation toward the Dual Alliance with Austria–Hungary.

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