Article on French Canadian immigrant and worker communities in the states of Michigan, Minnesota, Wisconsin, and Illinois in the nineteenth century. How farming, lumbering, and mining communities of this era differed from the fur-trading, French Canadian frontier establishments of the same region in the eighteenth century. Figures on the cultural and linguistic assimilation of French Canadian immigrants in the Upper Midwest US. How economic success or poverty, urbanity or rurality, related to the loss or persistence of the French language and customs in these immigrant communities. Provides maps of the region from the seventeenth through the nineteenth century, with markers for trading posts, area demographics, and migration routes.