First off, let me say that I'm new to Wikitree, and THANK YOU to everybody that is involved with this amazing group project called Wikitree!!!
With that said, I very strongly agree with Ellen's comment. I have seen records of my wife's family Surname, Winsor, dating back to 840AD. It is amazing to watch the various progressions the Winsor name has taken through all the various different branches of the family Lineage.
Also keep in mind that the majority people were illiterate until the last couple of centuries. The people that could read and write in 1000AD for ecample, were almost all people closely associated with wealthy, powerful and influential people of their era. So phonetics played a very important role in virtualy everybody's historical Surname. Especially when emigration took place from one country, to another, that spoke different language.
Honestly, accent and dialect differientials from say England to United States still get confused and can quite often cause misspelled words or names... to this day... Or even from one side of a country to another... LOL