| Ralph Herseth | |
| Order: | 21st |
| Office: | Governor of South Dakota |
| Term Start: | January 6, 1959 |
| Term End: | January 3, 1961 |
| Lieutenant: | John F. Lindley |
| Predecessor: | Joe Foss |
| Successor: | Archie M. Gubbrud |
| Birth Date: | July 2, 1909 |
| Birth Place: | near Houghton, South Dakota, U.S. |
| Death Place: | Aberdeen, South Dakota, U.S. |
| Party: | Democratic |
| Spouse: | Lorna Buntrock |
| Alma Mater: | North Dakota State University |
| Profession: | Farmer |
| Nationality: | American |
Ralph E. Herseth (July 2, 1909 – January 24, 1969) was the 21st governor of South Dakota from January 6, 1959, to January 3, 1961. He was a Democrat and was the patriarch of the prominent Herseth family of South Dakota.
Herseth was born in 1909 on a ranch near Houghton, South Dakota, the son of Oline (née Afseth) and Lars Herseth. His father was a Norwegian immigrant, as were his maternal grandparents.[1] [2] 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[3] 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 2004 until 2011.
Herseth was a Superintendent for the Civilian Conservation Corps (1935–39). He served in the South Dakota State Senate for Brown County from (1951–52) and (1957–58).
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.[4]
Herseth, died from a heart attack on January 24, 1969, aged 59, while visiting a friend at home in Aberdeen, South Dakota.[2] [5] He had a history of heart problems, having previously suffered a heart attack in 1960.[5] He is interred at Houghton Cemetery, Houghton, Brown County, South Dakota US.[6]