The thesis explores changes and continuities in the impostor phenomenon in England over the period c. 1500-c. 1770. Several historical developments can be said to have fostered a climate of social dislocation in which the language of deception and fraud became an important cultural phenomenon. Rather than following the discourse of imposture primarily through intellectual debates, the thesis focuses on social experience in a range of contemporary contexts. Drawing upon sources ranging from judicial archives and other official sources to chronicles, newspapers, pamphlets and autobiographical writings, the thesis investigates why someone might be considered an impostor and how he or she was perceived and represented. It asks too how the selfperception and fashioning of impostors - the shaping of their identities and stories, understood as a cultural practice - was influenced by their social environment. Part One focuses on the variety of impostors and their wider significance within the specific contexts of social, political, religious, institutional or cultural change. Part Two links the themes of imposture and autobiographical writing, and provides a micro-historical analysis of a notorious late seventeenth/early eighteenth-century impostor who during his lifetime assumed several different roles. By exploring these episodes as autobiographical practices, the thesis also contributes to the interdisciplinary debate on the nature of self-expression and individualism in early modern England.