Dublin is necessary to this book. It’s inextricably tied to Stephen’s discontentment and to his sins; immersion in a bustling, often squalid urban space heightens Stephen’s (and our) awareness of his physical sense. The dirtiness of the city contrasts the spirit of possibility that surrounds the few natural spaces we encounter (such as Stephen’s summer idyll at Blackrock and the open, outward-looking expanse of the sea). Notably, the character most untouched by the darkness, sensuality, and cynicism of the city is Davin, whose country roots keep him at a distance from urban dangers.
The political climate of turn of the century Ireland is also particularly important; there’s a perpetual undercurrent of sadness and anger at the lack of Irish independence that runs through the entire text. The argument between Mr. Casey and Aunt Dante at the beginning of the novel lays out some of the sources of political tension. The brief recap is that many Irish people felt like Charles Stewart Parnell was their best chance to gain "Home Rule," that is, autonomy from England. In contemporary terms, he was "a uniter, not a divider." But then Parnell made one little mistake: he had an affair with Kitty O’Shea, a woman who had already separated from her husband. This issue split the nationalist cause, with pious moralists (like Dante) on one side ("Think of the CHILDREN!") and pragmatic reformers on the other side ("Hey, what’s the big deal?"). The pragmatists, like Mr. Casey, were especially ticked off at the Church, which played a particularly vocal role in condemning Parnell. Some people even thought the Church was in cahoots with the British.
Overall, Stephen has mixed feelings about his hometown. He often seems to think that Dublin is hopelessly mired in the past and unable to modernize like the great cosmopolitan cities of Europe. He thinks its citizens are paralyzed by nostalgia and inaction – like his father, Simon Dedalus. On the other hand, he often finds beauty even in the dinginess of the red-light district, his cluttered home, or the seaweed he sees from the shore of the beach.