The debate over King Arthur is one of the oldest on record. But up until now all attempts to settle the debate have centred on interpretations of the documentation. But documents, as important as they are, are not the only tools at our disposal. History repeats itself. One of the reasons it does this is that there are a surprisingly large number of things that can only happen one way. Furthermore different societies do certain things in specific ways. Once it is known how these things work, then no documentation is necessary to explain what happened. There is enough information to determine the basic political and military systems the Britons used. It then becomes a matter of using this information to explain what is known of the course of the wars of this period to determine whether or not there is reason to believe that any such hero existed. But the system has other uses as well. Legends also work in specific ways. This technique can also be used to trace the origin of many of the figures and events in the legends.