Sorry, sorry, sorry.
This is what kings, students, unfaithful spouses, and loads of politicians have said.
The following list is by its nature incomplete.
We apologize for this.
Henry IV, 1077
With whom?
Pope Gregory VII
For what?
His resistance to the papal insistence on being allowed to appoint bishops in Henry's empire ("investiture controversy").
How?
By standing barefoot in a penitent shirt in front of Canossa Castle for three days.
What's the point?
The church ban is lifted again, Heinrich can continue, deposed Gregor and had a substitute pope crowned.