William Mutchler (father of Howard Mutchler) was born in Palmer Township, Pennsylvania. He attended the public schools and Vandeveer’s Academy in Easton, Pennsylvania. He studied law, was admitted to the bar and commenced practice at Easton. He served as sheriff of Northampton County, Pennsylvania, from 1854 to 1860, and as prothonotary of Northampton County from 1861 to 1867. He was adjutant of the Thirty-eighth Pennsylvania Volunteers in 1863. He was appointed assessor of internal revenue in March 1867 and served until May 1869. He was chairman of the Democratic State committee of Pennsylvania in 1869 and 1870, and a delegate to the Democratic National Conventions from 1876 until his death.
Mutchler was elected as a Democrat to the Forty-fourth Congress, where he served as chairman of the United States House Committee on Expenditures in the Department of the Interior. He was not a candidate for renomination in 1876. He was again elected to the Forty-seventh and Forty-eighth Congresses. He was not a candidate for renomination in 1884. He was again elected to the Fifty-first, Fifty-second, and Fifty-third Congresses, and served until his death in Easton. Interment in Easton Cemetery.
- United States Congress. "William Mutchler (id: M001125)". Biographical Directory of the United States Congress. Retrieved on 2008-02-14
- William Mutchler at The Political Graveyard
- William Mutchler at Find a Grave
- Memorial Addresses on the Life and Character of William Mutchler, a Representative from Pennsylvania. Washington, DC: US Government Printing Office. 1893. p. Frontispiece.