John M . Clayton ( Arkansas ) " This article is about the assassinated Arkansas Republican . For the U . S . Secretary of State and Senator from Delaware with the same name , see John M . Clayton . " John Middleton Clayton ( October 13 , 1840 – January 29 , 1889 ) was a Republican Congressman - elect in post - Civil War Arkansas . He may be best remembered for his mysterious assassination in 1889 . The identity of his assassin remains unknown . Biography . Clayton and his twin brother , William ( W . H . H . Clayton ) , were born on a farm near Chester , Pennsylvania to John and Ann Glover Clayton . His father was an orchard keeper and carpenter . His parents had ten children in all , although six died in infancy . Clayton went on to marry a woman named Sarah Ann with whom he had six children . During the Civil War , he served in the Army of the Potomac where he engaged in several campaigns in the east . In 1867 , he and his family moved to Arkansas where he managed a plantation owned by older brother , Powell Clayton , who would become the Governor of Arkansas the next year . In 1871 , Clayton was elected to the Arkansas House of Representatives representing Jefferson County , his brother , Powell , starting his term in the United States Senate the same year . In 1873 , he served in the Arkansas Senate representing Jefferson , Bradley , Grant and Lincoln Counties , also serving as Speaker of the Senate " pro tempore " for part of his term . He served on the first board of trustees of Arkansas Industrial University , today the University of Arkansas , when it was chartered in 1871 . Two years later , Clayton helped Pine Bluff , Arkansas secure the Branch Normal College , today the University of Arkansas at Pine Bluff . He became involved in the Brooks - Baxter War of 1874 which was fought over the disputed election for the governor ' s office between Joseph Brooks and Elisha Baxter . Clayton , a supporter of Brooks ' , raised troops in Jefferson County and marched them to Little Rock , Arkansas where they fought Baxter supporters . He remained loyal to Brooks to the end of the conflict when President Ulysses S . Grant declared Baxter the rightful governor . Clayton remained involved in Arkansas politics in the years after Reconstruction . With the support of black Republican voters , he became sheriff of Jefferson County in 1876 , being reelected to five successive , two year terms . In 1888 , he ran to represent Arkansas ' s 2nd congressional district in the United States House of Representatives , going up against incumbent Democrat Clifton R . Breckinridge . The election became one of the most fraudulent in Arkansas ' history . Clayton lost the election by a narrow margin of 846 out of over 34 , 000 votes cast . However , in one case in Conway County , four masked and armed white men stormed into a predominately black voting precinct and , at gunpoint , stole the ballot box that contained a large majority of votes for Clayton . Losing under such circumstances , Clayton decided to contest the election and went to Plumerville , Arkansas to start an investigation on the matter . On the evening of January 29 , 1889 , an unknown assailant shot through the window to the room he was staying in at a local boardinghouse and killed him instantly . He was later declared the winner of the election and Breckinridge was unseated and the seat declared vacant . His assassin was never found . Clayton was interred in Bellwood Cemetery in Pine Bluff , Arkansas .