Originally Posted by DocH
I think it came from the military. At Sandhurst, officer cadets were either "Rodneys" (who joined after school.... possibly from Grammar schools) or "Ruperts" (who joined after university ......probably came from public schools originally) . The RAF were considered slightly techie, so were named "Nigels"
ps.. which of course makes William a "Rupert" and Harry a "Rodney"