Walter Rasmussen founded the school in 1900 as the Rasmussen Practical School of Business, in Stillwater, Minnesota. Rasmussen believed the need for skilled professionals by the local business community was not being met. With the advent of women's suffrage in 1920 through the Nineteenth Amendment, the school’s female enrollment began to increase. In 1945 Walter Rasmussen retired and named Walter Nemitz to succeed him as director of the college. Nemitz had been with the college since 1934 and as director instituted a number of curriculum upgrades. By 1950, more than 22,400 students had graduated from the school. In 1961, Walter's sons Wilbur Nemitz and Robert Nemitz took ownership of the school. In 1974, Rasmussen College acquired the St. Cloud Business College, and in 1979 acquired the Northern Technical School of Business. In 1983, the school opened a campus in Mankato, Minnesota. More campuses were opened in Eagan, Minnesota (1989), St. Cloud, Minnesota (1997), Rockford, Illinois (2006), Lake Elmo, Minnesota; Eden Prairie, Minnesota; Blaine, Minnesota (2010), Topeka, Kansas (2013), Overland Park, Kansas (2013) and Green Bay, Wisconsin (2007), Mokena-Tinley Park, Illinois (2010) and Wausau, Wisconsin (2010).