William Carlile Arnold (July 15, 1851 – March 20, 1906) was an American Republican member of the U.S. House of Representatives from Pennsylvania.

He attended the public schools and Phillips Academy in Andover, Massachusetts.

He studied law, was admitted to the bar in Clearfield County, Pennsylvania, and practiced in Curwensville and Du Bois, Clearfield County, Pennsylvania.

He resumed the practice of law in Clearfield County and died in Muskegon, Michigan, while on a business trip.

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