If a New Yorker is from New York, an Angeleno is from Los Angeles, and a Liverpudlian is from Liverpool (file that under "weird but true"), a Dubliner is a denizen of Dublin, Ireland. All that to say, when your book's setting is in the title, you know that setting is going to be a big, big deal. Like the biggest deal in the whole stinkin' book.
Dublin is the capital of and biggest city in Ireland, and it sits just to the west of England, with whom it's had a pretty troubled relationship over the years. During the time Joyce was writing, Dublin was undergoing a lot of changes, and not all of them awesome.
The Act of Union in 1800 had abolished Ireland's parliament, and a struggle between those who supported the British rule of Ireland and Irish independence or "home rule" would continue—often violently—until independence was achieved in 1922.
Part of that early 20th-century struggle included cultural revivals of Irish language, mythology, and music, as we see in "A Mother" and "The Dead." But those attempts to preserve culture were often overshadowed by poverty, religious discord, and all kinds of other problems.
See, Joyce's Dublin was a city in conflict with its past and yearning for a future. As Joyce depicts it, though, many of the ways its people tried to escape their current conditions led to even worse extremes of paralysis, whether from their religious beliefs, moral traditions, or even just their station in life. Let's face it: it's tough to shake things up. Unfortunately that means that rather than being the proud, modern metropolis that tourists today might encounter, Dublin, at least as Joyce characterized it, was in grave danger of missing the boat.
The settings of the individual stories of Dubliners run the gamut. They take place in small houses, along the streets of Dublin's center city and its suburbs, and in seedy bars and restaurants. There are concert halls and crowded bazaars, quiet hotel rooms and raucous parties. You name it, we've got it.
But let's think of "setting" creatively, too. There are a few stories driven almost completely by dialogue, but these are the exception. In most, the internal thoughts and feelings of the main characters are the real setting of the story. This is where all the changes take place, and almost all of the action.
And here's the kicker: if the city of Dublin affects the minds and hearts of its citizens, there's almost no difference between the city and the minds of the people who live in it. Both can be hard to escape, and often full of disappointed hopes. Joyce's creativity in setting up this relationship between person and place allows these stories of paralysis to move us all the more.