The Treaty of Saint-Germain-en-Laye was signed on 10 September 1919 by the victorious Allies of World War I on the one hand and by the Republic of German-Austria on the other. Like the Treaty of Trianon with Hungary and the Treaty of Versailles with the Weimar Republic, it contained the Covenant of the League of Nations and as a result was not ratified by the United States but was followed by the US–Austrian Peace Treaty of 1921.
The treaty signing ceremony took place at the Château de Saint-Germain-en-Laye.