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 ,
Treaty of Mutual Cooperation and Security Between the United States and Japan To support that requirement, it provided for the continued presence of US military bases in Japan. The treaty also included general provisions on the further development of international cooperation and on improved future economic cooperation. The treaty has lasted longer than any other alliance between two great powers since the 1648 Peace of Westphalia. The treaty had a minimum term of 10 years. However, it provided that it would remain in force permanently unless one party gives one year's notice that it wishes to terminate it. The earlier Security Treaty of 1951 provided the initial basis for the Japan's security