Idaho's first white immigrants came from Utah, California, and Oregon in the early 1860s. By the end of the Civil War, the chief sources of immigrants were the southern and border states. Homesteaders from the Midwest, Utah, and Scandinavia arrived at the end of the 19th century.
Since 1960, immigrants have come largely from California. Idaho suffered a net loss from migration of 109,000 persons between 1940 and 1970, but had a net gain of 110,000 persons in the 1970s. During the 1980s, Idaho had a net loss of 28,000 persons from migration. Between 1990 and 1998, the state had net gains of 129,000 in domestic migration, and 15,000 in international migration. In 1998, 1,504 immigrants from foreign countries arrived in Idaho. The state's overall population increased 22% between 1990 and 1998, making it one of the fastest growing states in the US, superseded only by Nevada and Arizona for the same time period. In the period 1995–2000, 182,929 people moved into the state and 149,082 moved out, for a net gain of 33,847, most of whom came from California.