This topic has really gone on too long dealing with the crap of a few apologists who can't accept that when the Hebrew text says Ur of the Kasdim, that it means Ur of the Kasdim. The problem for the apologist of course is that the notion of an anachronism is so unpalatable, but let's face it, concocting exotic exit strategies is only going to leave more egg on the face of the apologist.
The Kasdim (Gr: Chaldaeans) were relatively new arrivals on the Mesopotamian scene. Their name rarely occurs before the 8th century BCE. In fact the name may come from lower Mesopotamia where it seems to relate to a town name and was applied to these people when they arrived in the area. They held power in Babylon when the Neo-Assyrian power to the north was starting to wane and emerged as the leading force in the area under Nebuchadrezzar, who was responsible for a large building campaign in Ur (hence the connection Ur of the Kasdim). This is plainly what is referred to in Gen 11. One has to try to invent other links such as with Urkesh or with Urfa (Turkish name for what the Greeks called Edessa and the locals at the time of Augustus called Orhay, or similar). Then they have to imagine some link between their revised Ur(something, Urfa, Ura, Urkesh, etc., never plain old Ur) and the Kasdim of southern Mesopotamia.
The apologetics of this effort are transparent. Why bother with it?
spin