 It has been used to support theories regarding the origin and location of the tribes in the list and the way in which the tribes were systematically assessed and ruled by others.Some historians have proposed that the Tribal Hidage is not a list of peoples but of administrative areas.The Tribal Hidage is, according to D. P. Kirby's description, "a list of total assessments in terms of hides for a number of territories south of the Humber, which has been variously dated from the mid-7th to the second half of the 8th century".