| Quote #1
The "Red Death" had long devastated the country. No pestilence had ever been so fatal, or so hideous. (1)
Poe makes no connection to reality in the beginning of his story. He does not tell us where the country that the Red Death devastates is located, nor when the story is set. And the disease he describes is a purely fictional one. We're immediately immersed in a different world, just vague enough to be a dream.
| Quote #2
This was an extensive and magnificent structure, the creation of the Prince's own eccentric yet august taste. (2)
We first learn that the Prince is the creative type, and apparently has a strange yet compelling taste. This is the first suggestion that he's an artist figure.
| Quote #3
There were buffoons, there were improvisatori, there were ballet-dancers, there were musicians, there was Beauty, there was wine. (2)
It's interesting that in the midst of the run of the mill pleasures of life, Poe also throws the arts – music, ballet, and, above all, Beauty (with a capital B – something Poe himself loved to write about). Prospero's abbey is not only a palace of pleasure, it's also a palace of art, and "Beauty."