Treaty of the Month: what historic international treaty has amused me this month?

This month: the secret Treaty of Björkö
Who, when and where
The Treaty of Björkö, also known as the Treaty of Koivisto in modern Finland, was a secret mutual defence accord signed on July 24, 1905 between Wilhelm II of the German Empire and Tsar Nicholas II of Russia.
Secret meeting
Prior to the signing of the mutual defense treaty, Wilhelm II arranged four days earlier to meet secretly with Tsar Nicholas II. On Sunday evening July 23, 1905, the Kaiser arrived from Vyborg Bay to Koivisto Sound in his yacht, the Hohenzollern. He dropped anchor near Tsar Nicholas' yacht, the Polar Star. This secret meeting is confirmed based on their discussions via telegram dubbed, "The Willy-Nicky Correspondence."

The overall defence treaty contained four articles and was signed by Wilhelm II and Tsar Nicholas II. It was countersigned by Tchirschky (head of the German Foreign Office), Count von Benckendorff, and Naval Minister Aleksey Birilyov.
Their Imperial Majesties, the Emperor of All the Russias on the one side, and the German Emperor on the other, in order to insure the peace of Europe, have placed themselves in accord on the following points of the herein treaty relative to a defensive alliance:
•    Art. I. If any European state attacks one of the two empires, the allied party engages to aid the other contracting party with all his military and naval forces.
•    Art. II. The high contracting parties engage not to conclude with any common enemy a separate peace.
•    Art. III. The present treaty will become effective from the moment of the conclusion of the peace between Russia and Japan and may be denounced with a year's previous notification.
•    Art. IV. When this treaty has become effective, Russia will undertake the necessary steps to inform France of it and to propose to the latter to adhere to it as an ally.
[Signed] Nicholas. William.
[Countersigned] Von Tschirschky. Count Bekendorf. Naval Minister, Birilev.

Why it has amused me
Although the treaty was signed by the Tsar in person, it was inevitably a 'dead letter' -as it has ubiquitously been coined, because of Russia's prior commitment to France through the Franco-Russian Alliance signed in 1892 which had the express intention of undermining the military supremacy of the German Empire in continental Europe. The Russian statesmen. the Tsars advisors including Prime Minister Sergey Witte and Foreign Minister Vladimir Lambsdorff, neither present at the yacht nor consulted beforehand, insisted that the treaty should never come into effect unless it was approved and counter-signed by France. The Tsar gave in to their pressure, much to the consternation of the Kaiser who did not fail to reproach his cousin:

"We joined hands and signed before God, who heard our vows!... What is signed, is signed! and God is our testator!"