Wow, there are some interesting perspectives regarding the lyrics of this song.
From my point of view it's not really about one particular person but the characteristics persons begining at a point in European history that had power, became corrupt and lost it. It is also being told collectively in hind sight.
Lastly, I believe it hints that history repeats it's self with the line "Oh, who would ever want to be King?" You would think that most people would not. But take a look around.