Hello, I answered the last part of your question here, talking about the central importance of Romanitas in post-Roman and early medieval Europe, specifically focussing on how the adoption of Roman culture and ambition was central to the image of succesful Anglo-Saxon kingship and nationhood.
Doing some research to see if others have asked this question, I found this thread, asked by /u/Funes1942 , but it doesn't look like the question was answered.