In 1948, four national polling firms infamously predicted that Thomas Dewey would win the presidential election by a comfortable 5 to 15 percentage points rather than the 4.4 percentage point victory won by President Harry Truman. This error brought the young polling industry to its knees.

Hmong refugees fleeing war in Vietnam and Laos began arriving in the United States in 1976 — many of them after fighting alongside Americans in the Vietnam War, or losing loved ones in that conflict Over the ensuing four decades, Wisconsin has become home to the nation's third-largest Hmong population following California and Minnesota.

For many Upper Midwesterners in the 21st century, not much could seem more familiar than the marks of Scandinavian influence on regional culture. But there was a time in North American history when Norwegians, Swedes and Danes were considered peculiar outsiders.

Policies based on eugenics — the notion that humanity can essentially speed up its own evolution by weeding out people with "undesirable" traits — were once widespread in the United States.