Saint Mary's County, Nevada Genealogy
Saint Mary's County, Utah Territory was organized 5 January 1856  from western parts of Weber, Desert, Tooele, and Juab counties. It was named for the Saint Mary's River, later called the Humboldt River. This county included all of present-day Nevada between 114° and 116° west longitude, and 39° 30' and 42° north latitude.Utah Territory was discontinued 2 March 1861 when Nevada Territory was created from part of Utah Territory. Part of the old Saint Mary's County became parts of present day Elko, Eureka, and White Pine counties. 
For records of Saint Mary's County (Utah Terrtory), see:
- Some records for old Saint Mary's County, Utah Territory may have been transferred to, or may have been re-recorded in the new counties formed from the old Saint Mary's. See also:
- "Chart of County Formation in Utah" in Division of Archives and Records Service at http://archives.utah.gov/research/guides/county-formation.htm (accessed 11 August 2011).
- John Koontz, Political History of Nevada, 5th ed. (Carson City, Nev.: SPO, 1965), 43-92. At various libraries (WorldCat). FHL Book 979.3 N2k
- Deon C. Greer, Atlas of Utah ((Ogden), Utah : Weber State College, 1981), 162, 164. At various libraries (WorldCat). FHL Q Book 979.2 E7a.
- "Counties of Nevada" in Nevada History: a Walk in the Past at http://nevada-history.org/county.html (accessed 7 August 2011).
- Handybook for Genealogists: United States of America, 10th ed. (Draper, Utah: Everton Pub., 2002), 688. At various libraries (WorldCat). FHL Book 973 D274 2002.