Why did Montresor invite Fortunato into the catacombs?

Our quite maniacal narrator, Montresor, ¨invites¨ Fortunato into his family catacombs on the excuse that he has purchased a pipe of Amontillado (rare, high quality wine), but that he now doubts its authenticity. It being the Carnival celebration, Fortunato is rather intoxicated and boasts that he can judge whether the wine is authentic.  In truth, there is no Amontillado.  Montresor has systematically planned to gain revenge on Fortunato, since he claims, ¨The thousand injuries of...

Our quite maniacal narrator, Montresor, ¨invites¨ Fortunato into his family catacombs on the excuse that he has purchased a pipe of Amontillado (rare, high quality wine), but that he now doubts its authenticity. It being the Carnival celebration, Fortunato is rather intoxicated and boasts that he can judge whether the wine is authentic.  In truth, there is no Amontillado.  Montresor has systematically planned to gain revenge on Fortunato, since he claims, ¨The thousand injuries of Fortunato I had borne as best I could, but when he ventured upon insult I vowed revenge.¨ It seems Montresor is so upset by these insults that he will not repeat them, even as he gloats about every other detail of his perfectly ironic murder/revenge.

However, we can guess that the insult might have been a slur that Fortunato uttered against Montresor's family name -- a matter of extreme pride for these upper echelon Italian men. Several times during their descent into the vault, Fortunato digs at Montresor´s social standing.  He causes Montresor to admit that his family is no longer ¨great and numerous,¨ and insultingly says that he cannot remember the Montresor family arms, so that our narrator must remind him.  Ironically, the victim does not catch on that the image of a snake biting the foot that stomps it d a theme of revenge in this family. Fortunato also taunts that Montresor has not been accepted into the secret society of the Masons, as he has.  Indeed, the victim is clearly a very pompous man, never imagining that his prideful expertise in wine is being used to lure him to his own death.

By the time they reach the bottom of the catacombs, we are convinced that the victim--drunk, boastful, openly calling a mutual acquaintance an ¨ignoramus¨--is indeed guilty of insulting Montresor.  Yet we observe with growing horror as the narrator describes his over-the-top revenge, and we are left to judge him a much more horrid man than Fortunato.