Law is not static; it changes constantly to suit the needs of the society which it regulates. However, this does not necessarily mean that the principles on which these laws are based change at the same speed. Where the Celtic laws are concerned, it seems as if the guiding legal principles remained quite similar over an extended period, from late prehistory into the Middle Ages. Of course, this does not imply complete co-identity of legal systems between the communities of late prehistoric Gaul and those of early medieval Ireland. Rather, it is a result of similar social, political and economic requirements of the societies governed by these laws, which seem to have been sufficiently similar across this rather large area in both space and time that made fundamental changes to the legal principles unnecessary.