Per the Family Tree website, here are the top libraries for genealogy research in the US:



Other regional libraries known for excellent Genealogy research especially for Scandinavian materials are: 

Arne G. Brekke Collection at UND  –  Grand Forks, North Dakota – these Bygdeboks contain history of Norwegian family farms

Decorah Genealogy Association – Decorah, IA

Museum of Danish America – Elk Horn, IA – contains a great deal of Danish genealogy resources

Minnesota Genealogical Library – Minneapolis, MN

Norwegian American Genealogical Center Naeseth Library – Madison, WI