How does the setting in A Streetcar Named Desire set the mood?
New Orleans is a city unique in the U.S. because of its cosmopolitan history; it is an old city, but did not become part of the U.S. until 1803. A mixture of cultures is present there. Its location in the deep South, the near-tropical climate, and the association of the city with the birth of jazz music all tend to contribute, in the mid-twentieth-century popular mind, to New Orleans symbolizing a degree of freedom and untrammeled desire that other American cities could not equal. The sensual and overheated quality of Tennessee Williams' art, made New Orleans the ideal setting for a play that explores themes not only of sexuality but also ones involving mental illness and unchecked human desire.
The city in its rawness also contrasts with the genteel atmosphere of Blanche and Stella's home, Belle Reve. The symbolism of that name ("beautiful dream") may be obvious, but Williams evokes this contrast between the southern countryside and the gritty urban setting of working-class New Orleans to highlight the desperation of Blanche, and her sense of loss in having to abandon the dream of her former comfortable life. It is partly the culture shock of moving from a rural to a harshly urban setting that, along with Stanley's brutal attack, drives Blanche into insanity at the tragic conclusion of the story.
The establishment of New Orleans helps to bring to light the fact that the South has definitely changed. From the upbringing of both sisters at Belle Reve to a modern metropolis like New Orleans, the South of the past has long since passed. In this light, the feeling of different worlds is evoked. Blanche's discomfort is also akin to the setting because she, too, is of a different time and world. The South that she knew is long gone and in its place is this new vision where she cannot be assimilated. The fact that the area of New Orleans in which Stella and Stanley live is working class or poor also brings to light the difficulty of this modern vision for someone like Blanche, who is used to the "finer things" or at least believes herself to be worthy of these elements. There is not much in way of happiness or contentment in this setting, and this helps to establish Blanche's emotional climate, where there is much unsettled and little that is constant.