What is the overall tone of The Mayor of Casterbridge?
Hardy's novels are famous for their bleak and unyielding view of the world and man's place in it. His expression of what he called the immanent will, which he characterised as a force that was profoundly indifferent or opposed to man, brings nothing but pain and sorrow to the characters in his works. This novel is no exception from this general rule. Consider what the following quote, which comes from the end of the novel, says about life and our place in it:
Her experience had been of a kind to teach her, rightly or wrongly, that the doubtful honour of a brief transit through a sorry world hardly called for effusiveness, even when the path was suddenly irradiated at some half-way point by daybeams rich as hers. But her strong sense that neither she nor any human being deserved less than was given, did not blind her to the fact that there were others receiving less who had deserved much more. And in being forced to class herself among the fortunate she did not cease to wonder at the persistence of the unforeseen, when the one to whom such unbroken tranquillity had been accorded in the adult stage was she whose youth had seemed to teach that happiness was but the occasional episode in a general drama of pain.
The way in which happiness is presented as "but the occasional episode in a general drama of pain" contributes to the rather pessimistic and depressing tone of the novel as a whole. Henchard's fate and his death as he dies alone and in obscurity seems to cement Hardy's view of life as being constructed mostly by moments of sadness and grief with the occasional interlude of happiness.