Thousands of Americans and immigrants moved to the area during the mining boom, prompting the federal government to create Fort Wilkins near Copper Harbor to maintain order. The first wave were the Cornish from Great Britain, with centuries of mining experience; followed by Irish, Germans, and French Canadians. During the 1890s, Finnish immigrants began settling there in large numbers, forming the population plurality in the northwestern half of the peninsula. In the early 20th century, 75% of the population was foreign-born.