into two major parts on the basis of some elements of their material cultures. It is probable that they originated from different areas and...there is no difficulty in imagining their ability to coexist. However, he also notes: One point that should be made at the outset is that there is no discernable difference in the culture- in the social anthropological sense- of the Grooved Ware and Unstan Ware people...it is only apparent from limited aspects of material culture and the evidence...shows it to have been subordinate to a tribal level of unity which took in the whole of Orkney. See also Prehistoric Orkney Ring of Brodgar Standing Stones of Stenness Maeshowe World Heritage Sites in Scotland Timeline of prehistoric Scotland Footnotes References Archaeology of Scotland Prehistoric Orkney Stone Age Europe Archaeological artefact groups