The story goes something like Patrick Henry was visiting England and, to snub him, the English put up a portrait of George Washington in the latrine for Henry to use. When Patrick Henry reemerged, he seemed unfazed and the English asked him what he thought. And Henry responded as /u/ungratefulgatsby said below.

It's an anecdote that Lincoln used to tell per Team of Rivals.

In the movie Lincoln, Daniel Day Lewis recounts a story involving, I believe, Patrick Henry eating dinner with the King of England and encountering a painting of Washington over a toilet. When the King asks Henry I'd he thought it was appropriate placement he replies "Yes, nothing will make a red coat shit quicker than the sight of George Washington". I have no idea if it's true or just part of the movie.