Answer:
Emperor Henry IV was the king of Germany during the time when Pope Gregory VII was pope. The pope felt it was his duty to make the Church as independent as possible, so he decided that he would take away the king's right of appointing a bishop using lay investiture. Henry IV said that that wasn't fair as he was the lord of his vassal bishops, so he should be able to appoint them a they are his lowers. Henry was then excommunicated then he had to repent to the Pope so the pope forgave him and Henry then became king again. He then lead an army to Rome and exiled the Pope. Then they had the Concordat of Worms which allowed the Church authority to appoint bishops and the Emperor to give them fiefs.
Step-by-step explanation: