The eighteenth and nineteenth centuries witnessed the simultaneous rise of two discourses that promised to explain the past and predict the future: probability and the novel. The two were not merely historically coincident. In dialogue from the start, "Probable Histories" argues that probability and the novel were also mutually constitutive. Drawing on standard histories of each, I summarize their respective "rises" in the eighteenth century and analyze their interdependence. I then turn to a series of case studies, investigating the novels of Henry Fielding, Charlotte Lennox, Walter Scott, George Eliot, Charles Dickens, and Thomas Hardy as points of intersection between the concerns of probability and those of the novel. The project reveals how these two modes of temporal projection extend and inform one another as modes of prediction. In so doing, "Probable Histories" offers a new account of the novel's shared role in conceptualizing causation.