Persuasion has three major settings: the country houses in Somersetshire where the novel begins, the village of Lyme Regis where the characters take a trip in the middle of the story, and finally the fashionable town of Bath, where everyone ends up. The novel sets up a strong contrast between the country and Bath: while the elder Elliots are just as snobbish at home, the broader social setting of the town gives them more opportunities to show off.
Bath also reveals the complexity of the class system in greater detail. The country splits up into three main levels: the mansions of Kellynch (first the Elliots and then the Crofts; go to "Symbols, Imagery, Allegory" for more on Kellynch Hall) and Uppercross (the Musgrove Srs.); the in-law apartments to the mansions of Kellynch Lodge (Lady Russell) and Uppercross Cottage (the Musgrove Jrs.); and trashy Winthrop (the unfortunate Hayters). And everyone, except Lady Russell, is related to each other by family or marriage. In contrast, Bath gives us a wide range of carefully-ranked abodes from the Dalrymples' luxurious digs in Laura Place all the way down to Mrs. Smith's rented room in Westgate Buildings, covering several separate but interlocking social circles.
We see this social geography in action when Sir Walter, faced with Anne’s stubborn refusal to blow off Mrs. Smith in favor of Lady Dalrymple, begins his rant by spitting out "Westgate Buildings! […] and who is Miss Anne Elliot to be visiting in Westgate Buildings?" (17.14). Sir Walter doesn’t need to know much more about Mrs. Smith than her address to think that he knows everything about her: that she is "old and sickly," and that a visit to her means "low company, paltry rooms, foul air, disgusting associations" (17.14). What’s interesting is that Sir Walter’s fantasy of Westgate Buildings is probably pretty accurate – does that justify his larger point about why Anne should give up Mrs. Smith for Lady Dalrymple? And could Sir Walter be hoist by his own petard here – are the Elliots of Camden Place different from the Elliots of Kellynch Hall?
So much for the setting in space – what about time? The novel even gives us the exact year and season in which it begins: "the summer of 1814" (1.18), just after Napoleon was defeated and exiled on the island of Elba, ending a decade of war between Britain and France. A new era of peace seemed to be at hand, and members of the navy were finally able to come ashore and restart their home lives. But in the early spring of 1815, just about the time the novel ends, Napoleon escapes from his island prison and stages a brief comeback, which ends for good a few months later with the Battle of Waterloo. So, that threat of future war that looms over the ending of the novel? It's not paranoia, but real historical context.