Efforts to recreate Celtic History and Culture must of necessity be somewhat speculative, falling closer to Cultural Anthropology than the kind of History, based on artifacts and written history, of the Greeks and Romans. Some of this owing to the fact that the Celts were a relatively unsophisticated people, scattered in tribes across a very diverse topography, and evolving no substantial written literature. Some of this is due to the steamroller effect of Roman Civilization and Conquest. Markale has used oral tradition, distribution of artifacts, and linguistic remnants to construct a theory. Whether one accepts the theory or not, it is based on comprehensive scholarship, and is well documented in his book.