My own personal response to this story is that this is a very clear allegory about the impossibility of trying to cheat death. The fantastical setting of the story, with a strong, supposedly impenetrable castle with revellers within and a terribly contagious disease outside is something that clearly lends itself well to a allegorical interpretation, and the theme of cheating death clearly emerges towards the beginning of the story:
With such precautions the courtiers might bid defiance to contagion. The external world could take care of itself. In the meantime it was folly to grieve, or to think. The prince had provided all the appliances of pleasure. There were buffoons, there were improvisatori, there were ballet-dancers, there were musicians, there was Beauty, there was wine. All these and security were within. Without was the "Red Death."
Notice how the sentences themselves try to separate Prospero and his lords and ladies from the Red Death, the virulent disease that destroys all in its path. The allegorical interpretation is only strengthened as the story continues and the appearance of death in the final black room results in the death of Prospero and the entrance of the Red Death into the castle, who had come "like a thief in the night." The story therefore acts as a salutory reminder that no matter how powerful, wealthy or important people are, they can never cheat death. This is a particularly important message for a society that is so focused on trying to erase the signs of aging and also trying to prolong life as much as possible. Death is an essential fact that cannot be ignored, and this short story reminds us of this sobering message.
"The Masque of the Red Death" does not seem like one of Edgar Allan Poe's best stories. It is not really dramatic. It seems like a tour de force intended to show off the author's learning and verbal skill. Here is one of many possible examples of pointless prose:
To the right and left, in the middle of each wall, a tall and narrow Gothic window looked out upon a closed corridor which pursued the windings of the suite. These windows were of stained glass whose color varied in accordance with the prevailing hue of the decorations of the chamber into which it opened. That at the eastern extremity was hung, for example, in blue—and vividly blue were its windows. The second chamber was purple in its ornaments and tapestries, and here the panes were purple. The third was green throughout, and so were the casements. The fourth was furnished and lighted with orange—the fifth with white—the sixth with violet. The seventh apartment was closely shrouded in black velvet tapestries that hung all over the ceiling and down the walls, falling in heavy folds upon a carpet of the same material and hue. But in this chamber only, the color of the windows failed to correspond with the decorations. The panes here were scarlet—a deep blood color.
It is a good thing that there are only seven rooms, or Poe might have run out of colors. This tedious, old-fashioned description for the sake of description became odious to more modern writers, including Mark Twain. There is really no great significance in one chamber being mainly blue with blue windows and another being purple with purple windows, etc. Since the Prince presumably picked out the colors and everything else himself, it would seem that he knew in advance that something bad was going to happen in the seventh chamber, because he had window-panes installed that were a foreboding "deep blood color."
The story, or etude, seems to have been written for readers who had much more time to devote to reading that do most people today. If most of the florid Gothic description were excised from this story, there would be little story left. Perhaps that was Poe's purpose in laying on so much frosting: to cover up the weakness of the plot. "The Masque of the Red Death" might be used as an example of what is bad about Poe's writing and why so many modern critics and teachers dislike him. He continues to survive in the "canon" because of his dramatic, intriguing stories, including "The Cask of Amontillado," "The Tell-Tale Heart," "The Black Cat," and his perhaps especially his highly influential stories of ratiocination, "The Purloined Letter," "The Murders in the Rue Morgue," and "The Gold Bug."