expansionist policies of the Emperor Frederick II, who aimed to unite his inheritance in the south (Sicily and southern Italy) with his acquisition of the Holy Roman Empire in northern Italy. He spent a great deal of time and energy attempting to gain control over Lombardy and Tuscany, which brought him into direct conflict with the Papacy. Frederick was repeatedly excommunicated by one pope after another. In order to drive off the Hohenstaufen, the Papacy contrived a deal with the brother of Louis IX of France, Charles of Anjou, Count of Provence, who was invited to Italy to assume the crown of Sicily and be a counterweight against the Empire. He was too successful, however, and the Papacy found itself in the deadly embrace of the Angevins. Nicholas' prime goal was to loosen Charles I's grip on the Papacy, Rome, and the lands of the Church. Nicholas' pontificate, though brief, was marked by several important events. He greatly strengthened the papal position in Italy. On 1 October 1273, Rudolph I of Habsburg, the godson of Frederick II, had been elected King of Germany and King of the Romans. Pope Gregory X had recognized him as King, after some hard negotiation, but the imperial title and coronation were withheld. Pope Nicholas was willing to negotiate, but he refused to crown Rudolf as Emperor until Rudolph had acknowledged all the claims of the Church, including many that were quite dubious. The concordat with Rudolph I of Habsburg was concluded in May 1278. In it the city of Bologna, the Romagna, and the exarchate of Ravenna were guaranteed to the papacy. According to the chronographer Bartholomew of Lucca (Ptolemy of Lucca), he discussed with Rudolph, in general terms at least, the splitting the Holy Roman Empire into four separate kingdoms – Lombardy, Burgundy, Tuscia and Germany – where Rudolph's kingdom would be made hereditary and he himself would be recognized as Holy Roman Emperor. Nicholas III was even able to persuade King Charles I of Naples and Sicily to give up his position as Roman Senator in 1278, at the conclusion of ten years of tenure, as well as the position of Papal Vicar for Tuscany. In July 1278, Nicholas III issued an epoch-making constitution for the government of Rome, Fundamenta militantis which forbade foreigners from taking civil office. It depends for its justification not only on the biblical phrase, "Tu es Petrus,