The Agaw are perhaps first mentioned in the third-century Monumentum Adulitanum, an Aksumite inscription recorded by Cosmas Indicopleustes in the sixth century. The inscription refers to a people called Athagaus (or Athagaous), perhaps from ʿAd Agaw, meaning sons of Agaw. The Athagaous first turn up as one of the peoples conquered by the unknown king who inscribed the Monumentum Adulitanum. The Agaw are later mentioned in an inscription of the fourth century emperor Ezana of Axum and the sixth-century emperor Kaleb of Axum. Based on this evidence, a number of experts embrace a theory first stated by Edward Ullendorff and Carlo Conti Rossini that they are the original inhabitants of much of the northern Ethiopian Highlands, and were either forced out of their original settlements or assimilated by Semitic-speaking Tigrayans and Amharas. Cosmas Indicopleustes also noted in his Christian Topography that a major gold trade route passed through the region Agau. The area referred to seems to be an area east of the Tekezé River and just south of the Semien Mountains, perhaps around Lake Tana.