The ninth century Historia Brittonum is the first source that mentions Arthur and lists twelve battles, including the famous Badon Hill. Much ink has been spilt debating the identity and location of Arthur. This book will demonstrate that some of the battles can indeed be located with some confidence. Rather than fit a specific theory as to his identity the battles are placed in the fragmenting provincial, political and military context of the late fifth and early sixth century Britain. At a time of rapid changes in cultural identity and a significant increase in Germanic material culture and migration.These battles might be expected to be found along borders and in zones of potential conflict. Yet this is not what is discovered. In addition the simplistic idea of Romano-Britons holding back invading Anglo-Saxons is found wanting. Instead we discover a far more nuanced political and cultural situation. One with increasing evidence of continuation of land use and the indigenous population. The most Romanised and urbanized regions of the south and east are the very areas that experienced the arrival of Germanic settlement. The conclusion gives the reader a new insight into what sort of man Arthur was and the nature of the battles he fought.