In Improbability, Chance, and the Nineteenth-Century Realist Novel, Adam Grener advances a new approach to evaluating realism in fiction by arguing that nineteenth-century literary realism shifted attention to the historical and social dimensions of probability in the period's literature. In an era in which probability was increasingly defined by statistical concepts of aggregation and abstraction, the realist writers discussed here turned to chance and improbability to address representational problems of contingency, difference, and scale. Contemporary thinking about probability came to recognize the variability and even randomness of the world while also discovering how patterns and order reemerge at scale. Reading chance as a tension between randomness and order, Grener shows how novels by Jane Austen, Sir Walter Scott, Charles Dickens, Anthony Trollope, and Thomas Hardy resist the demands of probabilistic representation and develop strategies for capturing cultural particularity and historical transformation. These authors served their visions of realism by tactically embracing improbability in the form of coincidences, fatalism, supernaturalism, and luck. Understanding this strategy helps us to appreciate how realist novels work to historicize the social worlds and experiences they represent and asks us to rethink the very foundation of realism.