The Minnesota Historical Society (MHS) is a private, non-profit educational and cultural institution dedicated to preserving the history of the U.S. state of Minnesota. It was founded by the territorial legislature in 1849, almost a decade before statehood. The Society is named in the Minnesota Constitution. It is headquartered in the Minnesota History Center in downtown St. Paul.
MHS currently holds a collection of nearly 550,000 books, 37,000 maps, 250,000 photographs, 165,000 historical artifacts, 800,000 archaeological items, 38,000 cubic feet (1,100 m3) of manuscripts, 45,000 cubic feet (1,300 m3) of government records, 5,500 paintings, prints and drawings; and 1,300 moving image items.
More information, including a list of state historical sites, on the Wikipedia page 
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