The name of the city of Oxford is virtually synonymous with that of Oxford University. At the time of its emergence in the historical record, however, the university had taken root in what was already a thriving medieval town. The broad, shallow floodplain of the river Thames had encouraged the development of a major river crossing at Oxford, and this crossing provided both a focus for a permanent settlement, and the name of Oxford by which the settlement came to be known. This volume presents a comprehensive account of archaeological research into the origins and development of Oxford, from the 7th century, when St Frideswide's Minster was established, through the subsequent development of Oxford as a Saxon burh, or centre of defence against the Vikings, until the end of the 12th century, when the existence of a fledgling university is first apparent. It includes reports on some 18 previously unpublished archaeological sites.The chapters are treated thematically, and cover the Thames Crossing, the defences, and the developing town with its streets, properties, houses and churches. Each report is preceded by a synthesis and discussion of the evidence, which traces the development of theories about the Anglo-Saxon town and reviews the many problems that still exist. This discussion is supported by a gazetteer of relevant archaeological observations in the historic core of the city. There is also a detailed review of the development of the river Thames and its floodplain at Oxford.