In many aspects, the Imperial claims to feudal overlordship over the Italian territories had become practically meaningless: the effective political authority, as well as the power to raise taxes and spend resources, was in the hands of the Italian princes and dukes. However, the presence of the Imperial feudal network in Italy continued to play a role in the history of the peninsula. It gave to Sigismund, Holy Roman Emperor and Maximilian I, Holy Roman Emperor the pretext to intervene in Italian affairs. Furthermore, the Imperial rights were notably asserted during the Italian Wars by Charles V, Holy Roman Emperor (also King of Spain and Naples, Archduke of Austria and Duke of Burgundy). He drove the French from Milan after the Battle of Pavia, and prevented an attempt by the Italian princes, with French aid, to reassert their independence in the League of Cognac. His mutinous troops sacked Rome and, coming to terms with the Medici pope Clement VII, conquered Florence where he reinstalled the Medici as Dukes of Florence after a siege. Charles V was crowned King of Italy with the Iron Crown in medieval fashion and, upon the extinction of the Sforza line of Milan in 1535, claimed direct possession of that territory as an Imperial fief. After Charles divided his possession between a Spanish and Austrian branch, Milan became a possession of the Spanish Empire of Philip II of Spain, whereas the title of Holy Roman Emperor and the rights connected to Imperial Italy were transferred to Ferdinand of Austria. Milan continued to be a state of the Holy Roman Empire so that, in his position as Duke of Milan, Philip II was, at least formally, a vassal of Emperor Ferdinand. However, following the reign of Charles V, no Holy Roman Emperor of the Austrian Habsburgs was crowned King of Italy and the title effectively ceased to be used for two centuries and a half.