William Frederick Milton Arny (1813–1881) was born on May 9, 1813 in the District of Colombia. He was the son of Joseph Arny from Krummenau, St. Gallen, Switzerland and Elizabeth Hyde (Joseph's first wife) from England.
Arny was the general agent of the National Kansas Committee, agent of the Utes and Jicarilla Apaches of Northern Mexico and a friend of Abraham Lincoln. Arny served as secretary of New Mexico Territory in the 1860s.
Arny also served as the agent dealing with the Navajo and has been described as "the worst agent the Navajos ever had to deal with"