He served as delegate for the Territory of Minnesota to the U.S. Congress from 1849 to 1853. Henry. Sibley was active in forming the legislation that established Minnesota as a state. He served as a delegate from July 7, 1849 until March 3, 1853. Henry Sibley served in the Territorial legislature of Minnesota in 1855 and served as the president of the constitutional convention for the territory in 1857.
In 1858, he was elected the 1st Governor of Minnesota after statehood. He served as Governor from May 24, 1858 to January 2, 1860. He was a Democrat.
Sibley County, Minnesota is named after him.