If you can find a copy of...
by Merriment Demon Heart (guest)
1/26/2004, 5:46 AM
either E.G. Withycombe 'Oxford Dictionary of English Christian Names' or Ernest Weekley's article 'Jack and Jill', they give instances of the first recorded usage of middle names in the UK. I'd quote 'em myself for you, but I'm not at home.