Berengar II of Italy
John soon found that he was unable to control the powerful Roman nobility as his father had so effortlessly done. At around the same time, King Berengar II of Italy began to attack the territory of the pope. In order to protect himself against political intrigues in Rome and the power of Berengar II, John sent papal legates in 960 to King Otto I of Germany, who had previously been granted the rank of patrician, asking for his aid. Agreeing to John's invitation, Otto entered Italy in 961. Berengar quickly retreated to his strongholds, and Otto proceeded to enter Rome on 31 January 962. There he met with John and proceeded to swear under oath that he would do everything to defend the pope: