Too often dismissed as the unready king—unprepared, ill-advised, and incapable of dealing with the military and political crises that faced the Anglo-Saxon kingdom, not least of which were a series of Viking onslaughts—King Aethelred has gone down in history as an incompetent failure. This new biography redresses the indictment, placing Aethelred into his proper historical context. Central to the study is the authoritarian manner in which the king ran the English kingdom for much of his reign. King Aethelred is shown to have made effective use of the infamous Danegel and to have demonstrated royal power on a number of occasions with devastating results. While there were mishaps, disasters, and family intrigue, Aethelred managed to come through these crises until the final Danish invasion of 1013. Illustrated and including original reconstruction paintings, this study gives an insight into the turbulent politics of a 38-year reign and addresses the manner in which King Aethelred used his authority as a medieval English monarch.