This was an international agreement signed in 1919 that ended wwi.

The Treaty of Versailles

Explanation:

In 1919, a little under a year after a ceasefire was ordered, the countries in the war (besides the Central Powers converged to formulate an armistice to "bring everlasting peace", and form the terms of the peace treaty imposed upon the nations of the Central Powers, including the break up of the German Empire, Austro-Hungarian Empire, and acquisition of many Ottoman Empire territories, forming independent nations, and establishing overseas territories for the victorious nations (think British Palestine, Japanese Qingdao, etc). This was all signed on 28 June 1919.