Antonio (The Tempest)

In William Shakespeare's comedy The Tempest (believed to have been written and performed circa 1610, but not published until 1623), Antonio is the brother of the wizard Prospero and is notable for having usurped his brother's position as Duke of Milan.

Origin
Antonio is a Milanese nobleman with Machiavellian ideals and lust for power. His brother Prospero, once the rightful the Duke of Milan, had great love and respect for him, so he made Antonio a Lord and trusted him to take care of Milan's political affairs while Prospero himself was occupied with his alchemical and magical studies.

Unfortunately, the treacherous Antonio enjoyed his position so much and became so convinced of being better suited to handle it than Prospero, that he secretly allied himself with the King of Naples, plotting to get rid of his brother and take the duchy for himself. In exchange, Antonio agreed to pay for Naples' help with tributes and favors, essentially subjugating Milan to the Neapolitan kingdom, much to the dismay of Prospero.

Since Prospero was such a beloved figure for the people of Milan, they decided not to execute him, but rather "exile" him by abandoning him on a damaged, unsailable boat at the sea, along with his three-year old daughter Miranda. Against all odds the two survived and ended up on the coast of a mystical uncharted island where Prospero, as a castaway, continued his magical studies and became an increasingly powerful wizard. Meanwhile Duke Antonio became a regular at the Neapolitan royal court and was among those invited to attend Princess Claribel's wedding in the distant kingdom of Tunis, in Africa.

When the royal fleet was returning to Naples after the wedding, they inadvertently passed close to Prospero's island. Sensing an opportunity for vengeance, the sorcerer ordered his faithful servant Ariel - a powerful air spirit - to create a tempest and engulf the king's ship in it, making it appear to the rest of the fleet that the ship had sunk. Meanwhile, Ariel hid the ship from sight and put the seamen to sleep with a spell.

Antonio was then brought to the island's shore along with the king Alonso, the king's brother Sebastian, the councilor Gonzalo and two other noblemen named Francisco and Adrian. Believing themselves to be the only survivors of the shipwreck, the group nevertheless sets foot in search of the king's son, Prince Ferdinand, as Francisco claims to have seen the prince swimming safely towards the shore (this was probably said only to raise the mournful king's spirit and give him some hope). In reality, Ariel had brought Ferdinand to a different part of the island where he eventually meets and falls in love with Prospero's daughter Miranda.

While the king's party travels through the island, the dry wit and sarcasm of Antonio and Sebastian becomes clear, as they mock the joyful optimist displayed by Adrian and Gonzalo. The ensuing bickering between them greatly annoys the king, who wants nothing but silence for the moment. At the same time, as Antonio truly believes Ferdinand to be dead, he starts planning another betrayal. Ariel, who had been hearing this conversation, puts everyone under a spell which causes them to fall asleep instantly, leaving only Antonio and Sebastian awakened. As soon as he sees this opportunity, Antonio convinces Sebastian that if he kills Alonso, the throne will be inherited by him and he will be king when they come back to civilization. Seeing that Antonio and Sebastian are indeed treacherous and about to commit regicide, Ariel wakes up Gonzalo, who immediately questions their intentions. The duo makes up an excuse that they had heard wild animals approaching and took swords to protect the king and the rest of the party, but it seems the king and Gonzalo become suspicious. Nevertheless, they proceed in their search for Ferdinand.

As they eventually exhaust themselves walking through the island, the group finds an unexpected banquet being served by beautiful nymphs and native spirits (who are servants of Ariel and Prospero). However, this is actually a ruse set up by Prospero, and as soon as they approach to eat, the food disappears and Ariel materializes, taking the form of a harpy to delivers a speech condemning Antonio, Sebastian and Alonso for what they did to Prospero and Miranda. The spectacle leaves the men insane, fencing their swords at the air in vain attempts to hit the immaterial spirits that torment them. At first, Prospero is pleased by this vengeance, but seeing the sadness and compassion in Gonzalo (who had greatly assisted him during the exile by secretly providing him with food and water) and even Ariel (who claims that he would feel pity for them if he was human) makes Prospero realize that his vengeance had come too far, and that it's nobler to forgive than to destroy. He thus breaks the spelling and returns the three men's sanity, and presents Alonso with the best of gifts: his son. He does also quietly warn Antonio and Sebastian that he's aware of their previous attempt to murder the king, but will keep it silent as long as they repent. As Alonso is convinced that Prospero had been wronged, he returns Prospero to his position as Duke of Milan and all return to the continent to attend the marriage of Miranda and Ferdinand.