There is a linguistic thread leading directly from hoi polloi, plethos and plenus to another Latin word, plebs, which we use disparagingly in English, but which in Ancient Rome was the official term for the lowest class in society and the direct opposite to the nobility or patricii
(ultimately related to words we have in English such as 'patrician' 'patriotic' 'paternal' and even 'father').
The phantom host is also found in an eleventh-century text, the Versus sancti Patricii
episcopi de mirabilibus Hibernie, composed by Bishop Patrick of Dublin sometime before his death by drowning in 1084.
The force of the argument is cumulative, and the claim for a Welsh literary tradition forms part of a larger argument, for which one must consult, inter alia, the author's The Celtic Latin Tradition of Biblical Style (Dublin, 1995) and Liber epistolarum Sancti Patricii
episcopi: The Book of Letters of Saint Patrick the Bishop (Dublin, 1994).