United States than Norway. Data from the U.S. Office of Immigration statistics of the number of Norwegians obtaining lawful permanent resident status in the U.S. from 1870 to 2016 highlights two peaks in the migration flow, the first one in the 1880s, and the second one in the first decade of the 20th century. It also shows an abrupt decrease after 1929, during the economic crisis of the 1930s. Settlement Beginning in 1836, Norwegian immigrants arrived in significant numbers annually. From the early "slooper" settlement in Illinois, Norwegian pioneers followed the general spread of population northwestward into Wisconsin. Wisconsin remained the center of Norwegian American activity up until the American Civil War, a war in which a number of Norwegian Americans fought for the Union, such as in the 15th Wisconsin Volunteer Regiment. In the 1850s Norwegian land seekers began moving into both Iowa and Minnesota, and serious migration to the Dakotas was underway by the 1870s. Norwegian immigration through the years was predominantly motivated by economic concerns. Compounded by crop failures, Norwegian agricultural resources were unable to keep up with population growth, and the Homestead Act of 1862 promised fertile, flat land. As a result, settlement trended westward with each passing year. The majority of Norwegian agrarian settlements developed in the northern region of the so-called Homestead Act Triangle between the Mississippi and the Missouri rivers. Early Norwegian settlements were in Pennsylvania, Massachusetts, and Illinois, but moved westward into Wisconsin, Minnesota, and the Dakotas. Later waves of Norwegian immigration went to the Western states such as Montana, Washington, Oregon, and Utah through missionary efforts which gained Norwegian and Swedish converts to Mormonism. Additionally, craftsmen also immigrated to a larger, more diverse market. Until recently, there was a Norwegian area in Sunset Park, Brooklyn originally populated by Norwegian craftsmen. The upper Midwest became home to most immigrants. In 1910 almost 80 percent of the one million or more Norwegian Americans lived in that part of the United States. In 1990, 51.7 percent of the Norwegian American population lived in the Midwest. At that time, Minnesota had the largest Norwegian American population and Minneapolis functioned as a hub for Norwegian American secular and religious activities. In the Pacific Northwest, the Puget Sound region, and especially the city of Seattle, became another center of immigrant life. Enclaves of Norwegian immigrants emerged as well in greater Brooklyn, New York, in Alaska, and Texas.