History is always impure. It is a mixture of truth, error, and uncertainty. It becomes tainted with the uncertainties and imperfections of the real world. After all, histories are written by humans.
History has power over us because we are blind to these impurities. All histories are imperfect. However, some are more imperfect than others. Some, based on reliable and objective reports, come close to indisputable truth. Others, based on unreliable or subjective sources, come close to absolute falsehood. It is not always obvious which are which.
The Frontier Fort in Georgetown falls into this zone of truthiness. The Poe brothers frontier adventures certainly do. I must have ten versions of the Poe brothers battle with the Indians. Each version tells a fascinating, yet oddly different, story.