In "The Masque of the Red Death," who is the stranger behind the mask?

This is, as many of Poe's short stories are, a very
symbolic piece of fiction, where you would be advised to look for how events, characters
and the setting operate symbolically. It is clear from the description of the uninvited
guest that he represents death and the way that no matter how hard we try, we are unable
to escape, cheat or run away from death. It is key to note that when Prospero challenges
this guest they are both standing in the blue room, and then the guest walks through all
the seven rooms (seven indicating the seven stages of life and the seven stages of man)
to the black room, symbolising the last stage of life. Note too that this guest is
seized when he is standing in "the shadow of the black clock," itself a symbol of time
passing and the brevity of life. This all points towards the guest as being "The Red
Death" itself, or death, that Prospero and his revellers were unable to
cheat.