In the 12th century the relationship between the pope and the Holy Roman Emperors was very strained. The king of the HRE (Holy Roman Empire) from the Hohenstaufen family was Frederick Barbarossa. He wanted to fight against the decentralizing that was happening in the HRE but to do that he needed the funds to control the provincial princes. The north of Italy was called Lombardy at that time and ruled by the former Lombard barbarians. It was very wealthy so Frederick decided to take control of Lombardy to use the funds. The pope disagreed with this and Lombardy did not want to be under German rule either. Frederick also supported anti-popes who were popes who were not elected by the college of Cardinals but also felt they had a claim to the title. At one time Frederick declared that if the people of the HRE did not support the anti-pope that their goods would be taken away then they would be hanged and drawn and quartered. He burned the city of Milan but eventually Lombardy pushed back on German rule and the pope and Frederick made up.
Frederick died in 1190 because he drowned while on crusade. At first a king from the opposing family, the Welfs, came to power but the pope, Alexander the third, soon deposed him because of his conquests in Italy. Then Frederick Barbarossa’s son, Frederick the second came to power. He had promised the pope to not unite the HRE with Sicily, because at that time Sicily was also under Hohenstaufen rule. Frederick the second quickly broke this promise and wanted to unite all of Italy under German rule because the Holy Roman Empire should contain the central part of the old Roman Empire. Frederick the second made continual conquests in Italy and eventually the pope deposed him at an ecumenical council due to killing clergy and robbing sees along with many other crimes.