Othello is partly to blame for his downfall as it is the way in which he distributes his trust, insecurity and jealousy which ultimately pushes him towards murdering Desdemona. Othello places too much trust in Iago which leads him to believe that Desdemona has been unfaithful. This can be seen in act 2 Scene 3 when Othello says; "Honest Iago, that look'st dead with grieving, / Speak, who began this?" This highlights how Othello places such trust in Iago that he will take his word on who began the fight, which results in Othello relieving Cassio of his duties.
Another reason why Othello is to blame for his downfall is because of his insecurities which lead him to believing that Desdemona has been unfaithful. In a way one could understand that Othello was simply waiting for Iago’s promting and for his own dream of happiness to come to an end because in his mind (probably due to years of prejudice converting to self hate) Othello has already deemed it impossible for someone of Desdemona’s position to ever fully loving him so when the push comes, Othello is fully prepared to play judge and executor of the one person he loved above all else.
While Othello’s feelings have attributed to his downfall, it was his ensign Iago who was eaten up by hatred and jealousy that ultimately caused his downfall. Shakespeare portrays Iago as cynical, quick-witted and opportunistic which are all traits of villains in revenge tradgedies. Iago explains in Act 1, Scene 3, how 'Virtue' is 'A fig!' and ''Tis in ourselves that we are thus, or