I do not approve of you, emperor, of choosing the bishops. I believe I should since I am the pope myself.
Well, my opinion is important as well, of course. However, I am the emperor of this country and I will decide this situation.
Back in the Middle Ages, all the way in 1073, there was two powerful leaders that had much power in Rome. There names were Pope Gregory VII and the Holy Roman Emperor Henry IV. However, they didn't get along at one point in time, and it resulted in many consequences.
I order you to remove Pope Gregory as pope, as for he questioned my authority.
I, Pope Gregory VII, has excommunicated you from the church, and you will be overthrown by the empire's nobles.
One day, Pope Gregory VII and the Holy Roman Emperor Henry IV were negotiating amongst each other inside the castle. Talking about who will choose a important choice of selecting bishops that will serve in their country. This is the pope's argument.
Henry IV listened carefully of what Pope Gregory VII was strongly disapproving of the emperor choosing the bishops. So Henry IV answered with what his opinion was in this whole conflict.
Thank you, Pope Gregory! I will never be angry at you ever again.
I have accepted your apology, and I will let you back into the church and castle.
After that great argument of Pope Gregory proving that his authority matters more in this situation than Henry's, Henry then got really mad when the pope showed this, so he ordered the Germany Bishops to remove him as pope. However, Gregory responded with something very crucial.
After getting excommunicated, Henry desperately needed to get back his power so he can save himself and his people in his country from going to Hell when they died. So begging for forgiveness, he stayed barefoot in the snow, right in front of the castle, for three days, trying to get the pope to talk to him.
Finally after three days, Pope Gregory accepted Henry's forgiveness and allowed him back inside the church, proving that messing with Pope Gregory can cause great consequences, even if you're the Holy Emperor of your country.