The Wisconsin Territory was established by the Federal Government effective 3 July 1836, and existed until its eastern portion was granted statehood (as Wisconsin) in 1848. Therefore, the Federal Government set up the Minnesota Territory effective 3 March 1849. The newly organized territorial legislature created nine counties across the territory in October of that year. One of those original counties, Itasca, had its eastern section partitioned off on 20 February 1855 into two new counties: the western part was designated Newton and the eastern part was named Superior County. The territorial legislature returned to the matter on 3 March, changing Superior County to Saint Louis County. Then on 1 March 1856, the county name was again changed, to Lake County, and the "Saint Louis County" name was given to the previous Newton County. With the new name came the designation of county seat at Beaver Bay, which had first been platted in 1856. The county's boundaries were altered in 1874, when its eastern part was partitioned off to create Cook County.