Well, some Englishmen were observed closely in an Italian environment once -- was it Edmund Spenser? -- un inglese italianato e un diabolo incarnato.
Doesn't get much more derogatory than that, unless it's the old German college-boy canard that "Englishmen are dogs, and have tails". Sounds like the perfect invitation to a mooning.
Um, no -- Roger Ascham (d. 1568), tutor to Elizabeth I.