The Perpetual Accord is a peace treaty and alliance of the Acht Orte of the Old Swiss Confederacy and Duke Sigismund of Austria. King Louis XI of France was elected as a mediator between both parties. The negotiations took place in Constance. The first version was finalized on 30 March 1474, but had to wait until early 1475 for the ratification of the final version.
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Perpetual Accord Wikipedia(Text) CC BY-SA