lost Crete, Venice's largest and richest overseas possession. Venice experienced one last great martial triumph by helping to defeat the Ottoman Empire in the war of 1683–1699. By the 18th century, economic activity dwindled as the city withdrew in on itself and fell into stagnation, becoming easy pickings for the French revolutionary armies in 1796. The Papal States also lost much of their former power as the Protestant Reformation divided Europe into two camps. The remaining Catholic princes increasingly sought to be the masters in their own houses and often clashed with the papacy over jurdistrictional matters. During the unceasing rivalry between France and Spain, Europe's two great Catholic powers, the popes often acted as mediators. Relations with Paris deteriorated sharply during the reign of Louis XIV, until he and the papacy found common ground in suppressing Jansenism. Even in Italy itself, the political importance of the Papal States declined. The Counter-Reformation popes largely concerned themselves with religious matters and church reform, and so had little time for politics. They worked to fight brigandage, long endemic in the Papal States, reformed the court system, and embellished Rome with many buildings. Gregory XIII introduced the calendar that bears his name, and the papal fleet participated in the Battle of Lepanto. In addition to its loss of political power, the Church came under increasing attack during the Age of Enlightenment in the 18th century. As Spain declined in the 16th century, so did its Italian possessions in Naples, Sicily, Sardinia, and Milan. Southern Italy was impoverished, stagnant, and cut off from the mainstream of events in Europe. Naples was one of the continent's most overcrowded and unsanitary cities, with a crime-ridden and volatile populace. The Neapolitan aristocracy long resented Spanish rule and welcomed the arrival of the Austrians in 1707. However, they were disappointed as Vienna continued the practice of not allowing any autonomy to Naples. While the war raged, Austria imposed huge tax burdens on the city and did not begin to provide it with any adequate administration until peace returned. Graf von Daun (viceroy of Naples from 1713 to 1719) attempted several reforms, but came into dispute with the church over jurisdictional matters. He largely succeeded in making peace with Rome, but international strife caused the Austrian emperors to impose more taxes on Naples and neglect all but the city's traditional feudal lords. Cardinal Michael Friedrich von Althann next became