Under what circumstances do toponymns (i.e. place names) of the indigeneous population get preserved despite an otherwise complete language shift somewhere?
One place where this could be determined almost entirely from historical records would be the Americas, where language shift happened (sometimes more than once, e.g., in Florida) in the post-Columbian era. There are places where pre-Indo-European place names are common (e.g. Long Island, New York), and others where they are rare.
Has anyone made a map demonstrating where they are and are not common, and has anyone written any scholarship discussing how this happened?
It seems like a various obvious kind of project to carry out particularly in light of the fact that there are a couple of European studies, at least, that have done just that (if I recall correctly, in the 19th century), but perhaps it would have been too daunting prior to the age of "Big Data."
The indigeneous place names have, presumably, been in place for a very long time, and this isn't the kind of research that absolutely requires tools that weren't available in the colonial era. So, it would be a shame to jump into a project looking at the issue if it has already been done. But, I wouldn't even know where to begin to locate something like that, other than to find a few likely Dewey decimal or Library of Congress numbers and to start browsing in a very large library.
Citations to kinds resources, if they exist already, would be welcome.