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This entry was originally written by Carol L. Maki and Michael John Neill for Red Book: American State, County, and Town Sources.
Naturalization records are located at the district court office of the county or at the Minnesota Historical Society Research Center. Availability varies by county and will continue to shift as more counties transfer their files to the center. Supreme court naturalization records (1858–1906) are found at the center. After 1906, naturalization was granted by the U.S. Federal District Court.