In the mid-19th century, Norwegians left their homeland to escape overpopulation, food shortages, and farm foreclosures, and began arriving in Minnesota in the 1850s, drawn by rich farmland and job opportunities. Some first settled in Wisconsin before moving into southeastern Minnesota, where they formed rural communities anchored by Lutheran churches that served as social and religious centers and visible links to Norway's traditions. As these farming settlements expanded, newcomers moved onto the prairies of central and western Minnesota, and after the railroad reached Moorhead in 1872, Norwegian immigrants poured into the Red River Valley, where as the earliest and most numerous group of European settlers they quickly became leaders in business and local affairs. In the 1880s and 1890s, as good farmland grew scarce, many found work in commercial fishing on the North Shore of Lake Superior or in the cities and iron ranges, laboring in mills, mines, and domestic service. As their numbers grew across the state, they established schools, fraternal societies such as the Sons of Norway, political organizations, and businesses that helped create a distinct Norwegian-American culture, while writers including O. E. Rolvaag and Martha Ostenso wrote of Norwegian-American experience. Supported by an active Norwegian-American press, they rose to prominence in Minnesota politics, religion, and higher education, helping make Norwegian Americans the state's third largest ethnic group and Minnesota a national cultural center for them. Although immigration quotas, the Great Depression, and World War II slowed new immigration, Norwegian-American culture remains strong in Minnesota today, sustained by organizations, the Norwegian-American Historical Association in Northfield, and continuing interest in this heritage.