Migration has long been recognised as an important driver of economic, social and demographic change. It is both a response to, and a determinant of wage rates, it acts as a vector of disease and it shapes our sense of place. Yet a paucity of data has meant that a comprehensive analysis of internal migration in nineteenth-century England and Wales has not been possible. The recent release of the Integrated Census Microdata (I-CeM) database - containing approximately 160 million individual-level returns - means that the given place of birth of the entire population as reported in the 1851-1911 censuses of England and Wales can be used to map millions of lifetime migration paths. By analysing the changing relationship between migration, wages, the transport network and the socio-economic context, it will be possible to understand both the determinants of migration and the effect it had on the communities migrants exited and entered over a sixty year period. The period 1851-1911 was also one in which migration fundamentally changed the profile of the British population. 1851 was the first year in which more than half the population of England and Wales were recorded as urban (50.4%) and just sixty years later, this had risen to 78.9%, almost trebling the urban population from 10.6 million to 28.2 million. Therefore, this study will provide deeper insights into the mechanisms driving individuals' migration choices which manifested themselves in the form of rapid urbanisation. It will address such questions as; if migrants were responsive to wage differentials, why did rural-urban migration peak when agricultural wages were high? What impact did the growing railway network have on migration flows? Did migration tend to occur within clearly defined boundaries? What does this tell us about individuals' sense of place? This study will be conducted in two strands and the first will consider individuals' incentives to migrate and wage differentials - to be transcribed from Board of Trade wage surveys - while the second will analyse migrants' capacity to move. In addition to analysing the effect of straight-line distance on migration flows over time and space, the transport network as it existed in 1831 and 1911 will be analysed thanks to a collaboration with my proposed mentor Dr Leigh Shaw-Taylor and his project 'Transport, Urbanization and Economic Development in England and Wales c. 1670-1911'. Analysing individuals' incentives to migrate in the context of factors limiting their capacity to do so allows radically new questions to be asked. Was time a more significant determinant of migrants' destination than distance once wage differentials are accounted for? Did this change as the network evolved? In order to account for migrants' constrained choice of destination, an algorithm developed with colleagues at MIT as part of my PhD will be used to identify migration fields - regions in which the number of moves within them was maximised and the number of moves between them was minimised. How did these regions shape individuals' choice of destination? By analysing the relationship between migrants' assessment of the risks and returns of leaving their parish of birth in the context of competing alternatives, the mechanisms which led to urbanisation and rural depopulation can be better understood and serve as a benchmark for further analyses of urbanisation in both the past and present. The outputs will be delivered by depositing the enriched sources with the UK Data Archive and by journal articles, a monograph, academic presentations, workshops for potential users and a small conference, publicising the project and encouraging new analyses. Outside academia online resources will be developed for schools, family/amateur historians and the public. These online tools will facilitate studies of migration which fulfils national curriculum requirements for projects in local history and geography in Key Stages 2-4.