The largest wave of Kieffer immigration likely occurred during the 19th century, particularly between 1830 and 1900. Factors driving this migration included economic hardship and lack of opportunity in German states, political unrest, especially following the failed revolutions of 1848, and the promise of free or cheap land in America, particularly after the Homestead Act of 1862. Many Kieffers settled in states with large German-American populations, such as Pennsylvania, Ohio, Wisconsin, and Missouri.