Before Christ's crucifixion Pilate's soldiers '...clothed him in a purple cloak, and plaiting a crown of thorns they put it on him. And they began to salute him, "Hail, King of the Jews!"' (Mark 15: 17-19).
This aspect of the mocking of Christ has often been painted, but such paintings are not always intended as narrative - the purpose is sometimes to create a sorrowful and at times iconic image, which can form the object of devotion.