The theme of this novel is the way modernity clashes with—and ultimately refreshes—the old ways of life of the village of Mellstock. Fanny Day, the protagonist, is the symbol of modernity. She shocks the village, for instance, when she becomes part of the Mellstock choir, and when her organ, also representing modernity, is introduced into the choir.
She manages as well to make her own choice of a marriage mate, bringing her father around to the idea of her marrying the man she loves, Dick Dewey, who her father doesn't think is good enough for her. Foreshadowing the way the suffragists in England would get the vote in part by refusing to eat, Fanny refuses (or pretends to refuse) to take any food. And although she is temporarily tempted by a marriage offer from the high-status vicar, Mr. Maybold, like a modern woman, she opts to follow her own heart and stay with Dick.
The novel is a pastoral romance, meaning it is set in the country and depicts the world in an idealized way. In this idyll, modernity is not a threat but a boon to Mellstock.