Herseth was born in Houghton, South Dakota, the son of Oline (née Afseth) and Lars Herseth. His father was a Norwegian immigrant, as were his maternal grandparents. He graduated from Columbia High School, in Brown County, South Dakota. He attended Northern State Teachers College and North Dakota State College. He married Lorna H. Buntrock on December 23, 1937, and they lived on a ranch near Houghton. Lorna Herseth later became South Dakota's Secretary of State. Their son Lars Herseth was Majority Leader of the State Senate, and granddaughter Stephanie Herseth Sandlin served in the U.S. House of Representatives from 2005 until 2011.
Herseth was only the third Democrat to hold the office of Governor of the state of South Dakota. As governor, he focused on state tax problems, appointing a Citizens Tax Study Commission to recommend tax reform. He was also active in developing South Dakota's natural resources. Big Bend Dam on the Missouri River was begun during his single term in office. The state government experienced problems resulting from hard-hitting natural disasters in South Dakota in 1959; he was defeated for reelection in 1960, and for a return to office in 1962.
Herseth died on January 24, 1969, and is interred at Houghton Cemetery, Houghton, Brown County, South Dakota USA.
- "Ralph Herseth". National Governors Association. Retrieved 2 September 2012.
- Ralph E. Herseth (Soylent Communications)
- "Ralph Herseth". Find A Grave. Retrieved 2 September 2012.
- Ralph E. Herseth entry at the National Governors Association
- Ralph E. Herseth entry at The Political Graveyard
- Ralph Herseth at Find a Grave
- Governor Ralph Herseth portrait
|Governor of South Dakota
January 6, 1959 – January 3, 1961
Archie M. Gubbrud