I have another theory about those place names from hundreds of years ago that refer to places we recognize as being in the U.S. I've found lots of them, and I believe they occur when people just add information to their trees without thinking as they go. You will note that ancestry.com often pops up place names in their database and then you can just click on them to add them quickly to your own information. Since many places in the U.S. were named after places in Europe or elsewhere in the world, these also pop up as you add information from centuries ago. I've found many of them, and as someone else said, I just correct them as I come upon them. For example, I just learned yesterday that "Maine" was a region (county?) in old France as well as a U.S. state. I have learned also to now pay close attention to place names when adding to my own trees.