Cinlipiuc is the Old Welsh spelling of Cynllibiwg (See Welsh Forms). The Red Book of the Exchequer (a list of, amongst other things, landowners from the 12th C onwards) has "In the time of Rhys ab Owain 'Between Severn and Wye' was called Cynllibiwg (Kenthlebiac)"*. Rhys ab Owain ruled from ~1072/1075 to 1078 CE*, though this does not in any sense negate the name being older as the spelling suggests. Paul Remfry** gives a detailed discussion of this region.