Alright, well, it was officially over when the armistice was signed on November 11, 1918. That marked the end of hostilities. The peace treaties of 1919, such as the Versailles Treaty, promised an accounting of the war. But it was only a couple weeks ago that the war reparations charged to Germany in the Versailles Treaty were fully paid off. See CNN’s story for the full details. (And thanks, Nick, for this reference).