This study explores pre- and extra-marital relationships among the gentry and nobility of the north of England from 1450 to 1640: the keeping of mistresses, the taking of lovers, the birth of illegitimate children and the fate of those children. It challenges assumptions about the extent to which such activities declined in the period, and hence about the impact of Protestantism and other changes to the culture of the elite. A major contribution to the literature on marriage and sexual relationships, family, kinship and gender, it is aimed at an academic readership in the fields of social and political history.