The island of Cyprus has important mythological significance as it has long been associated with Venus, the goddess of love. The action of The Tragedy of Othello moves to Cyprus when the Turks invade Venice, leading Othello and Desdemona to flee to the military encampment in Cyprus where they mistakenly believe their safety can be assured. Symbolically, this move to Cyprus is significant because the safety of Cyprus is a false one; Othello and Desdemona ironically lose their lives in a place where they were originally hoping to be safe. Another layer to the irony of this move relates to the fact that Iago's manipulation and his goals to ruin both Othello and Desdemona and to poison their love for each other are successful on an island that should be sacred to lovers thanks to its link to Venus.

A key point about the action moving to Cyprus, I believe, involves the issue of Othello's military prowess and his loyalty to the Venetians.

Venice, and Europe as a whole at the time Othello takes place, felt vulnerable to attacks by the Ottoman (Turkish) Empire. The relatively recent fall of Constantinople, one of the last major outposts of the remnant of the eastern Roman (or Byzantine) Empire, was a shock to Europe. Othello, in spite of his non-European background, is a major part of the Venetian (and by extension European) effort to block the Ottoman advance and to protect the European continent.

In the second act it is revealed that a naval battle has taken place, and that the Venetians have defeated the Turkish forces. Othello's military ability, demonstrated here, is important to the action of the play, partly because it makes him an ideal husband to Desdemona for every reason despite the racist objections to him that have been raised. This demonstrates the wrongness of the racist views held by Brabantio and exploited by Iago.

In some sense the play can be seen as a metaphor of the conflict between European and non-European cultures. The setting in Cyprus, an island in the eastern Mediterranean which partakes of both cultures, is emblematic of that conflict. Othello himself is tragically caught in the middle, as a man of non-European descent giving his loyalty and love to the Venetians and to Desdemona.

The transition of setting from Venice to Cyprus puts Othello outside the immediate control of Venician authority and Desdemona beyond the disapprobation of prating Brabantio. It is the 'fleshing out' of sorts of their free will.  An isolated military outpost symbolises both deliberate alienation from the norm and independance from control. Also, such liberty from primary influence serves as the vehicle for their respective natures to fully evolve and take hold.

But is such liberty too much? Here Othello's rashness and credulity- his double tragic flaw - is not held in check, for the 'veracity' of Iago and the sincerity of his friendship are never even put in question. As for Desdemona, her will melts before her idolation (and idealization) of her husband and she falls prey to Iago's perverse machination. She can no longer counter or even contest Othello's accusations once he is emported by rage. A subtle polarization of temperament has taken over. Whereas Desdemona weakens, Othello's hotheadedness now takes full rein and he loses control, he loses Desdemona, and he loses his life.

Why is Othello sent to Cyprus?

In Act 1, Scene 2 of Shakespeare's Othello, amidst all of the accusations and outrage towards Othello's marraige to Desdemona, Othello is called into a meeting with the Duke of Venice about official state business. The Duke has recieved word that a large number of Turkish ships are approaching the island of Cyprus- though the exact number of ships is desputed. Othello is then deployed by the Duke to Cyprus to defend the island because Othello is the general of the Venetian army. You should also note that the entire rest of the play takes place in Cyprus. I am attaching a link to the Othello reference page, which includes not only summaries and character analysis, but the entire text and stradegies for reading it, as Shakespeare's language can get quite flowery and difficult to understand at times. 

Why might Shakespeare decided to set Othello in Cyprus, an isolated outpost of the Venetian trading empire?

Why might Shakespeare decided to set Othello in Cyprus, an isolated outpost of the Venetian trading empire?

Iago may have more opportunity to manipulate Othello on Cyprus than in Venice. In Venice, Othello would be surrounded by many more people who know him. These people might have been able to give him advice about his wife (since many there would know her, too) and might have beeen able to counteract the influence of Iago. On Cyprus, Othello is relatively isolated from friends other than Iago, who is, of course, not a true friend at all.

Why might Shakespeare decided to set Othello in Cyprus, an isolated outpost of the Venetian trading empire?

Cyprus was a vital island, prone to attack due to its position. The island of Cyprus could be said to symbolize Othello himself: it is distinct from Venice though a valued part of its empire. Similarly, Othello is not a Venetian but is a very important part of the strategic defence team protecting the nation. Also, Othello is prone to attack -from Benvolio at the beginning of the play and by evil Iago throughout.

In Othello why does Shakespeare move the setting of the play to Cyprus?

The Turks were the ultimate enemy of Venice and Cyprus at the time of Othello. This allows Shakespeare some licence to vary his plot a little and move the story from the safety of Venice to the unknown realm of Cyprus. Shakespeare has been known for moving the action of his plays- such as in Antony and Cleopatra it moves from civilized Rome to unrestrained Egypt. In A Midsmmer Night's Dream, the magical world outside the seat of logic and reason is chosen to conduct much of the action.  

News has come to the Duke that a turkish fleet is headed for Cyprus and it is therefore necessary to send an army to defend it. Ironically it is Iago who is entrusted with Desdemona's safe passage there to meet her husband.

Consider Othello himself - although not a Venetian, he is a well-respected, decorated soldier. He moves from the civilized world of Venice where self-control is expected of him to a seemingly more passionate, unruly island. At first, even Othello's and Desdemona's behavior towards each other on the island is different and they are more relaxed and carefree. Othello is confident and arranges

a feast to honor the defeat of the Turkish fleet and to celebrate his marriage to Desdemona.

Othello then changes from a respected, self-controlled individual to one obsessed by jealousy.  

The drama that precedes the arrival on the island  “the wind-shaked surge, with high and monstrous mane,” a possible foreshadowing of what is to follow, adds to the drama and the potential of the island.

Desdemona is away from the safety of her family in Cyprus. She is passive and virtuous and her helplessness is reinforced by her presence on the island.

There are therefore several considerations regarding the setting. there's also the question as to whether Othello would have behaved in the same manner had they never left venetian society.