While browsing the Bodleian library, I came across this strange version of Lord Bateman, which seems to have been transliterated into (possibly) the old Cockney dialect, for no obvious reason (Particularly as it was printed in Durham!)

Examples:

Lord Bateman vos a noble lord...

Vere he vos taken and put in prisin..

This Turk he had one only darter...

O in sevin long years I'll make a vow

Full text here
The loving ballad of Lord Bateman