Who is sitting and watching what?
That would be the Emperor Nero. He is watching a group of Christian martyrs about to be burned alive, as allegedly, they were the perpetrators of the Great Fire of Rome.
The painting is called Pochodnie Nerona ( Nero's Torches ) by Henryk Siemiradzki. On display In Kraków.
You didn`t warn us about it. :)
Well, I just presumed you would know that they would be in Poland - sorry!
Yes, your answer is correct, gold star awarded, I will have to move on to the next difficulty level with my riddles :)