Interestingly, this play had at its basis the germ of a real story very similar to the plot of the play. In 1947, Miller was researching a story about a Longshoreman who had been executed by the mob for attempting to revolt against Union leadership in a context of mob justice and where a number of immigrants worked and lived. He was told another story about another Longshoreman who had informed the Immigration Bureau about his own relatives so that he could prevent the marriage of one of his own brothers and his niece. As a result of going against the community, this man was widely scorned and ostracised and in the end disappeared. However, a rumour circulated that suggested he had been killed by one of his own brothers for goign against his own family and community.
Thus it is that the idea for this play was born. Obviously, the overtones of incest that are present in Eddie's relationship with Catherine are Miller's own addition, but in this play he tries to capture the same group mentality and the power of the community which Eddie defies and suffers the consequences of when he informs on Marco and Rodolpho.