celebrate the festive carnival, Montresor executes his murderous plot. The fact that Montresor initiates his evil plan in the midst of a joyous occasion contributes to the horror of the story as the audience recognizes that nowhere is safe from a determined enemy. The carnival setting also allows Montresor to inconspicuously approach Fortunato, who is too intoxicated and distracted by the merry atmosphere to recognize that he is in grave danger.

After the characters travel to Montresor's palazzo, the setting shifts to his extensive catacombs, which are extremely dark, damp, and cold. Inside Montresor's vaults, nitre hangs from the ceiling; skulls and bones line the walls, and various wine bottles are scattered on the floor. The setting creates an ominous, eerie mood, which reflects Montresor's malicious intentions and foreshadows Fortunato's fate. The further they travel down the vaults, the darker the setting becomes and the more Fortunato isolates himself, increasing his vulnerability and playing perfectly into Montresor's hands. Once Fortunato reaches the end of the catacombs, Montresor quickly shackles him to the back wall and builds a rampart around his body. The story's horror reaches its climax when the audience realizes that Fortunato will be buried alive in the depths of the catacombs, where no one will hear his cries or come to his aid.

Montresor specifically chooses the carnival as a setting for his murderous plans to help conceal his crime. In this way, setting is crucial to the plot.

As Montresor spots Fortunato in the streets of the festival, he notices that the man is already feeling the effects of an alcoholic celebration:

He accosted me with excessive warmth, for he had been drinking much.

This demonstrates Montresor's knowledge of the way Fortunato would participate in the festivities. Fortunato's propensity for alcohol also means that his judgement is already impaired, and he will be less likely to ask questions that could ruin Montresor's plans.

The festival also provides a means for festive dress. Symbolically, Fortunato is also wearing a "conical cap and bells," or a clown's hat. This represents Fortunato's foolish trust in Montresor's devious plans.

Montresor knows that Fortunato has a "weak point" in his pride of wine connoisseurship. Because of the festival, mentioning his own supposed doubts about a cask of Amontillado is a particularly easy means of diverting Fortunato into the man's eventual place of death.

The festival also provides Montresor with a means of getting rid of everyone who might witness him entering the family's catacombs, thereby ensuring there are no witnesses to his crime:

There were no attendants at home; they had absconded to make merry in honor of the time. I had told them that I should not return until the morning, and had given them explicit orders not to stir from the house.

In short, Montresor is able to utilize the festivities of the carnival in combination with his knowledge of Fortunato's weaknesses and exploit both for his murderous plans. He correctly predicts that Fortunato will be so wrapped up in the festivities that his judgement will be impaired, and Montresor is thus able to lead him to an eerie catacomb because of Fortunato's pride.

The story is set largely in catacombs underneath Montresor's home in Italy.

The setting contributes significantly to the horror of the story. It is dark, cold, and damp in the catacombs. Because catacombs are burial vaults, Montresor and Fortunato pass by piles of bones, the remains of dead bodies. Nitre, a chemical irritant to the lungs when inhaled, lines the walls. As Montresor explains to Fortunato:

The vaults are insufferably damp. They are encrusted with nitre.

Montresor will later say of the nitre:

It hangs like moss upon the vaults. We are below the river’s bed. The drops of moisture trickle among the bones. Come, we will go back ere it is too late. Your cough——”

Montresor's words add to the horror, as the nitre poses a particular problem for Fortunato with his weak lungs. The catacombs also offer a sharp contrast to the revelry of the Carnival, where crowds of people are partying up above. Montresor and Fortunato are all alone in the catacombs, far away from any noise but what they themselves make and far from any possibility of being heard. This creates the perfect environment for Montresor to wall up his enemy.

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The setting of "The Cask of Amontillado" is in Italy during the carnival season.  Even more specific than that, the bulk of the plot takes place in the vaults, cellar, or catacombs beneath the home of Montressor, the story's main character and narrator.  The most important detail of the setting that contributes to the horror or suspense of the story is the fact that the two main characters, Montressor and Fortunado, are walking through a vault underneath Montressor's family mansion which holds the dead remains of his ancestors. 

For some aspects of the setting (in both time and place) of this story, we have to use the narrator's clues to make an educated guess. For example, although the narrator doesn't give us a specific date for when the action of the story occurs, he gives us a very good clue:

It was about dusk, one evening during the supreme madness of the carnival season, that I encountered my friend.

From this description, we can infer that Montresor, the vengeful narrator, meets Fortunato at about 5:30 p.m. on or near the last day of the Carnival season, which would be the Tuesday before Ash Wednesday: the beginning of Lent, forty days before Easter.

Given the names of the main characters, Montresor and Fortunato, as well as the fact that Carnival (the Italian name for the pre-Lent celebration) is being celebrated, it is reasonable to assume that the geographical setting is Italy. More specifically, because the most famous Carnival celebration in Italy is held in Venice (which, in the thirteenth through seventeenth centuries, was known for its internal political and social intrigue), we can also reasonably believe that Venice is the city in which the story is set. The specific setting of Fortunato's death, of course, is in the vaults or catacombs underneath Montresor's palazzo. This is where Montresor's ancestors are buried, as we know when Fortunato announces, “I drink . . . to the buried that repose around us."

Montresor and Fortunato are friends, but clearly Fortunato has incurred Montresor's wrath for an unspecified "insult" that is even more serious than the "thousand injuries" Fortunato has inflicted on Montresor before. Later in the narrative, we begin to understand Montresor a bit better when we see that the motto of the Montresor family is “Nemo me impune lacessit,” which loosely translates as, "No one harms me and goes unpunished." Montresor's vengeance against Fortunato is simply a family tradition. Fortunato is characterized by Montresor as

You are rich, respected, admired, beloved; you are happy, as once I was. You are a man to be missed. For me it is no matter.

This somewhat disguised bitterness on Montresor's part indicates that although these families were once equal in social status, Fortunato is now above Montresor's station, and as the Montresors appear to have been an intensely proud family, Montresor feels this difference keenly. The friends' different social status undoubtedly increases the severity of the "insult" felt by Montresor, who has become trapped by his vengeful nature. For his part, Fortunato is a pompous dilettante. This is evident when the two are in the vaults and Fortunato makes a Masonic sign, which he believes Montresor cannot understand:

“You do not comprehend?” he said. “Not I,” I replied. “Then you are not of the brotherhood.”“How?” “You are not of the masons.” “Yes, yes,” I said; “yes, yes.” “You? Impossible! A mason?”

Fortunato, in scoffing at Montresor's joking comment that he, too, is a mason (because he's going to use a trowel to bury Fortunato—he's a stonemason), is attempting to remind Montresor that he is no longer equal to Fortunato.

The setting of this story is Venice, in Italy, but most particularly, the catacombs --what were once underground graves--beneath Montresor's home. Think of the characters as going through a series of dark, underground tunnels or caverns, lit only by the flame of their torches. Near the end of their journey, we do see piles of bones from old corpses.

The time is the Mardi Gras, the festival that occurs the day before Lent, so probably February. The story takes place 50 years before Montresor, on his deathbed, is telling it, but the year is not specified.  

The story has only two characters who are part of the action: Montresor and Fortunato. They have known each other for many years. Both love fine wines. Montresor feels he has suffered injuries, and worse, insult, from Fortunato, so he wants revenge: he wants to kill Fortunato in some way so that Fortunato knows Montresor is the murderer but nobody else finds out. Fortunato shows that he is proud of his knowledge of wines. He is also drunk and easily tricked by Montresor. 

The setting of the story is very important to create the spooky mood that contributes to the horror.  Notice that the scene is first described as being almost dark.

It was about dusk, one evening during the supreme madness of the carnival season, that I encountered my friend.

It is dusk, which is a spooky time of night.  The impending dark symbolizes impending doom.  The carnival season is described as “supreme madness,” which reinforces the idea that there is chaos and a lack of inhibition about.  This kind of environment is conducive to wickedness. 

Local customs are part of the setting too.  The carnival season in Italy allows people to not be themselves.  Fortunato is dressed in motley, like a clown, with “tight-fitting parti-striped dress” and a “conical cap and bells” on his head.  He is drunk, because it is a party.  All of this contributes to the strange macabre juxtaposition of gaiety and grimness.

The sense of horror is increased as things get darker and the scene moves underground.  When Montresor lures Fortunato into the catacombs, we know that trouble is coming.

I passed down a long and winding staircase, requesting him to be cautious as he followed. We came at length to the foot of the descent, and stood together upon the damp ground of the catacombs of the Montresors.

The winding staircase, the shining torches, and the damp ground of the tomb are all specific details of the setting that contribute to horror.  The catacombs are tunnels underground that were used as tombs.  Montresor’s family uses this catacomb.  Since we already know that Montresor wants to get revenge on Fortunato for some undescribed injury, we can only guess that no good will come of this.

It is because it is carnival and no one will miss them, and because they go deep underground at dusk, that Montresor is able to murder Fortunato and make sure that no one will find the body.