The Old Swiss Confederacy a "de facto" independent state throughout the early modern period, although still nominally part of the Holy Roman Empire until 1648 when the Treaty of Westphalia ended the Thirty Years' War. The Swiss Reformation divided the confederates into Reformed and Catholic parties, resulting in internal conflict from the 16th to the 18th centuries; as a result, the federal diet () was often paralysed by hostility between the factions. The Swiss Confederacy fell to invasion by the French Revolutionary Army in 1798, after which it became the short-lived Helvetic Republic. The adjective "old" was introduced after the Napoleonic era with ,
Eighty Years' War Roman Empire of 14 and 24 October 1648, which comprise the Peace of Westphalia, but which were not signed by the Republic, the Republic now also gained formal "independence" from the Holy Roman Empire, just like the Swiss Cantons. In both cases this was just a formalisation of a situation that had already existed for a long time. France and Spain did not conclude a treaty and so remained at war until the peace of the Pyrenees of 1659. The peace was celebrated in the Republic with sumptuous festivities. It was solemnly promulgated on the 80th anniversary of the execution