The Amish Make the Map

Here's a map showing counties in the US where at least 10 percent of the people speak a language other than English, and the language. 

So looking at it, you can see the French Cajuns in LA and New England, the Navajos in the Four Corners., the Portuguese in New England, Chinese in Tompkins  County, NY (Cornell University) and Massachusetts, etc.  Several counties scattered around (MT, WI, OH, NY, IA) have either German or similar languages.  At first I was thinking German immigrants, since my grandfather was part of an influx to Wisconsin in the 19th century, but then I realized the data most likely reflects the Amish/Mennonite communities.