One of the problems that has bedevilled much discussion of crime in the past has been the lack of consistency in its categorization. In this thesis a systematic attempt has been made to resolve these difficulties and to provide a categorization based principally on an analysis of contemporary jurists. It is further argued that it is essential to consider the state of the criminal law in the seventeenth century in order properly to appreciate the subtleties of the law and thus the framework within which prosecution occurred. This framework is important in showing how. contrary to received belief. the criminal law in the period was comparatively sophisticated. This was the case. not only in theory. but also in practice. and it is a major contention of this thesis that the complexities of the law were recognized by contemporaries. and. indeed. affected the practices of prosecution. Most work on crime in the past has. to date, concentrated on the counties of the Home Circuit. close to. and doubtless influenced by. London. but in this thesis the material that exists in abundance for the Northern Circuit has been utilized to provide a picture of the pattern of crime. or rather of prosecution. in Yorkshire. From this it has been possible to see that the pattern was, in many ways, similar to that elsewhere. but that there were also significant differences. in particular a very high proportion of offences against the authorities. The chronological spread of the prosecution of crime has also been analysed and again it is plain that Yorkshire did not witness the decline in prosecution that might. from other studies. have been anticipated to have occurred by the end of the seventeenth century. The different influences on prosecution have also been considered and in particular it has been shown that central government initiatives were of considerable significance in affecting the prosecution of certain offences, especially those which impacted directly on the state, such as sedition and coining.