When I was in the Navy it got to the point I could tell which part of which state people were from. I've lost the talent but I can identify native Mainiacs up here and the occasional Long Gilander.
Indiana and Illinois and even Ohio are great states for dialect. You can draw a line where glaciation stopped. North of it those who mine the minerals it dragged down speak very differently from the crowd of descendants of those who moved west from the south leaving fallowed the land they left.
Pockets of Pennsylvania are infested with migrant groups who decided the eastern shore (probably Boston) weren't worth living in and other pockets are infested with stubborn Germans who called themselves Deutsche long enough they became the Pennsylvania Dutch. Some of them are Yoders, who refuse to become like the rest of the country until it becomes like them. Each has it's own dialect. Ted' you are mistaken about them all being Yoders, you just can't detect their real surnames, like Smith, Roberts, and Miller, due to the dialect.