Milton Speer "Mit" Simms, son of Maria Louisa Speer and Franklin Robert Simms, was born in Rockford, Alabama in 1873 and grew up there.^[1] He moved to Arizona Territory sometime before 1902. On December 25, 1902, he married his first wife, Lillian Mary McCabe (1881–1941). No children emerged from this marriage.

Mit Simms
Simms sometime in the 1910s
2nd State Treasurer of Arizona
In office January 6, 1947 – January 3, 1949
Governor	Sidney P. Osborn Dan Edward Garvey
Preceded by	J. W. Kelly
Succeeded by	William T. "Bill" Brooks
In office January 7, 1935 – January 4, 1937
Governor	Benjamin Baker Moeur
Preceded by	W. M. Cox
Succeeded by	Harry M. Moore
In office January 5, 1931 – January 2, 1933
Governor	George W. P. Hunt
Preceded by	Charles R. Price
Succeeded by	W. M. Cox
In office January 4, 1915 – January 1, 1917
Governor	George W. P. Hunt
Preceded by	David F. Johnson
Succeeded by	David F. Johnson
2nd Secretary of State of Arizona
In office January 7, 1919 – January 3, 1921
Governor	Thomas Edward Campbell
Preceded by	Sidney Preston Osborn
Succeeded by	Ernest R. Hall
Personal details
Born	Milton Speer Simms Aug. 12, 1873 Rockford, Alabama
Died	July 22, 1957 (aged 83) Phoenix, Arizona
Political party	Democratic

On September 12, 1910, he was elected Graham County Delegate to the Arizona Constitutional Convention. There, on December 9, 1910, he signed the Constitution of Arizona. He served as the 2nd Treasurer of Arizona for four non-consecutive terms from 1915 to 1917, from 1931 to 1933, from 1935 to 1937, and lastly from 1947 to 1949. He also served as the 2nd Secretary of State of Arizona from 1919 to 1921. He then served on the Arizona Corporation Commission from 1949 to 1954, and again from 1955 to 1957.

Simms failed runs include one for governor in 1920, where he lost to incumbent governor Thomas Edward Campbell in a nationally Republican year. He also ran for secretary of state in 1936^[2] and 1938,^[3] but lost in the Democratic primary both times, first narrowly to incumbent James H. Kerby, and the second time to fellow Treasurer Harry M. Moore. Simm also ran for treasurer in 1942,^[4] but lost in the primary to James D. "Jim" Brush in a four-way race, narrowly coming in second.

Throughout his life he was a dry goods salesman, a Graham County recorder, a farmer, and a rancher.^{[citation needed]}

On May 15, 1946, Simms married Sarah Loella Wright.^[1] Their marriage lasted until his death. She lived until August 23, 1969.^{[citation needed]}

He died on July 22, 1957, at St. Joseph's Hospital in Phoenix, Arizona. His body was buried on July 25, 1958, in the Safford Union Cemetery in Safford (Graham County).^{[citation needed]}