 Ireland continued as a <unk> of rival kingdoms but , beginning in the 7th century AD , a concept of national kingship gradually became articulated through the concept of a High King of Ireland . Medieval Irish literature portrays an almost unbroken sequence of High Kings stretching back thousands of years but modern historians believe the scheme was constructed in the 8th century to justify the status of powerful political groupings by projecting the origins of their rule into the remote past . 
