Many of the ceremonial, routine, and even martial activities of a people are influenced by their beliefs and stories. These stories, once we learn them, may tell us why they buried their dead, reveal the significance of the Moon in their religious observances, and lend insight concerning their decisions to attack other peoples.
Consider, for instance, that the ancient Mayans used annotated stone tablets with the cycles of the universe emblazoned on them. It could be that they simply kept an extraordinarily well-defined calendar; on the other hand, they may have believed that their devotion to time-keeping also displayed loyalty to one or another of their gods. If we fail to understand which it was, we take the information of the tablets to mean something completely foreign to the intentions of the Mayan priests and astronomers. This would be unfortunate.
Why is it that many ancient burial grounds, while not rising to the level of sophistication of the modern graveyard in its orderliness, displayed human remains with their heads oriented to the east? Presumably, their people interred them with their heads toward the rising sun, which was seen either as the parent of their people or as one of their chief gods. Again, it is better for us to study these ancient grounds and attempt to understand their meaning rather than simply to assume we know all of the answers in advance.
Mythology of the early humans we call Homo Heidelbergensis may tell us why many of the bodies were buried with stone artifacts that still would have been useful to those who survived. Additionally, was it mere sentimentality that compelled family members to place pretty flowers with some of the deceased, or did they have a mythological belief that required such a gesture? It might tell us more about the mental and psychological development of early humans were we to learn the answers to these questions.
It is said that wars are fought by people who would rather be doing almost anything else, but consider the effect of a firmly-held myth that required frequent attacks on one's neighbors as a way of appeasing a deity. Did early humans hold such beliefs, or was their "warfare" largely based on simple survival, "either you die, or I will die"?
Archaeology and history are informed by a studied understanding of what various ancient civilizations and groups convinced themselves, in view of their myths, they must do. None of these need be based on a foundation that we might recognize as rational; some of our own mythology lacks rationality. It is very important to look at why people did what they did, thereby gaining knowledge of who they really were, not simply where and when they lived, fought, and died.