What groups of people moved into the midwest region from 1800 to 1880?

Several groups moved into the Midwest region of the US between 1800 and 1880.  

Yankee farmers were the first settlers to arrive in significant numbers. They brought much of New England culture into the new territories and contributed to the development of towns and cities, most notably Chicago.

Other groups that arrived in the area were Scandinavians, Irish Catholics, German protestants, German catholics, Lutherans, English-Canadians, Dutch, Swiss and British.

a.) it weakened the power of the catholic church in europe.