jun 28, 1919 - The Treaty of Versailles
It was the most important of the peace treaties that brought World War I to an end. The Treaty ended the state of war between Germany and the Allied Powers. It was signed on 28 June 1919 in Versailles, exactly five years after the assassination of Archduke Franz Ferdinand which directly led to World War I. The other Central Powers on the German side of World War I signed separate treaties. Although the armistice, signed on 11 November 1918, ended the actual fighting, it took six months of Allied negotiations at the Paris Peace Conference to conclude the peace treaty. The treaty was registered by the Secretariat of the League of Nations on 21 October 1919.
Added to timeline:
Timeline on WW1