Soon other powers began to exploit Austria's weakness. Charles VII claimed the inheritance to the hereditary lands and Bohemia, and was supported by the King of France, who desired the Austrian Netherlands. The Spanish and Sardinians hoped to gain territory in Italy, and the Saxons hoped to gain territory to connect Saxony with the Elector's Polish Kingdom. France even went so far as to prepare for a partition of Austria. Austria's allies, Britain, the Dutch Republic, and Russia, were all wary of getting involved in the conflict; ultimately, only Britain provided significant support. Thus began the War of the Austrian Succession (1740–1748), one of the more confusing and less eventful wars of European history, which ultimately saw Austria holding its own, despite the permanent loss of most of Silesia to the Prussians. That represented the loss of one of its richest and most industrialised provinces. For Austria the War of Succession was more a series of wars, the first concluding in 1742 with the Treaty of Breslau, the second (1744–1745) with the Treaty of Dresden. The overall war however continued until the Treaty of Aix-la-Chapelle (1748). In 1745, following the reign of the Bavarian Elector as Emperor Charles VII, Maria Theresa's husband Francis of Lorraine, Grand Duke of Tuscany, was elected Emperor, restoring control of that position to the Habsburgs (or, rather, to the new composite house of Habsburg-Lorraine), Francis holding the titular crown until his death in 1765, but his empress consort Maria Theresa carrying out the executive functions. The Pragmatic Sanction of 1713 applied to the hereditary possessions of the Habsburgs and Archduchy of Austria but not the position of Holy Roman Emperor, which could not be held by women, thus Maria Theresa was Empress Consort not Empress Regnant. Seven Years' War and Third Silesian War (1756–1763) For the eight years following the Treaty of Aix-la-Chapelle that ended the War of the Austrian Succession, Maria Theresa plotted revenge on the Prussians. The British and Dutch allies who had proved so reluctant to help her in her time of need were dropped in favour of the French in the so-called Reversal of Alliances (bouleversement) of 1756, under the advice of Kaunitz, Austrian Chancellor (1753–1793). This resulted in the Treaty of Versailles of 1756. That same year, war once again erupted on the continent as Frederick, fearing encirclement, launched a pre-emptive invasion of Saxony and the defensive treaty became offensive.