By 1652, it was considered ruined and unrecognizable. This may explain why someone decided later to knock a hole right through the base of Jesus to make room for a door.
Just so we're clear how much of a mess this was, this is the 15th century Catholic Italy we're talking about. Jesus was sort of a big deal over there.
Then Napoleon, a great lover of art and anything Leonardo, came along and decided it was shit. When his troops were stationed in Italy, he decided to turn the whole room into a storage closet. Then, because he wasn't quite finished dragging his ass all over Leonardo's second greatest work, he decided to turn it into a prison.
By 1826, after a number of attempts to fix it, an attempt was made to move it to a safer location. Unfortunately, they commissioned a man who specialized in moving frescos to move The Last Supper. That'd be great if it was actually a fresco. His techniques ended up damaging the painting, and he quickly tried to glue the whole thing back together, which only added to the damage.
Clearly, The Last Supper. Or an out of focus photo of some laundry. We're not sure.