Shortly after the United States had completed the
Louisiana Purchase, officials began to survey the territory at a site near the intersection of Monroe,
Phillips, and
Lee counties. From forested
wetlands in what would become southern Monroe County, approximately of land would be explored after President
James Madison commissioned a survey of the purchase area. The point was commemorated in 1961 by the
Arkansas General Assembly as part of
Louisiana Purchase State Park. Settlement in Monroe County began when Dedrick Pike settled in 1816 where the
Cache River enters the
White River. The settlement was named Mouth of the Cache, and a post office by that name was opened years later. The community renamed itself
Clarendon in 1824 in honor of the
Earl of Clarendon. Monroe County was established under the
Arkansas territorial legislature in 1829, and the
county seat was established at
Lawrenceville, where a jail and courthouse were erected. A ferry across the White River was founded in 1836. In 1857 the county seat was moved to
Clarendon, Arkansas. The new brick courthouse was nearly finished by the outbreak of the
American Civil War in 1861. The county sent five units into
Confederate service. After
Union troops captured Clarendon in 1863, they destroyed the small city. The Union had completely dismantled the brick courthouse and shipped the bricks to
De Valls Bluff. After the war, during Reconstruction, there was a high level of violence by insurgent whites seeking to suppress the rights of freedmen and to keep them from voting. After Republican Congressman
James M. Hinds was murdered by George Clark, a Democrat and member of the
Ku Klux Klan in Monroe County in October 1868, Governor
Powell Clayton established
martial law in ten counties, including Monroe County, as the attacks and murders were out of control. Four military districts were operated for four years in an effort to suppress
guerrilla insurgency by white paramilitary groups, such as the Ku Klux Klan and others. They continued to challenge enfranchisement of blacks and the increasing power of Republicans in the county. The
Monroe County Sun newspaper was established in 1876. Violence continued after Reconstruction, when Democrats had regained control of the state legislature. Whites struggled to re-establish white supremacy, by violence and intimidation of black Republican voters. At the turn of the century, the state legislature passed measures that effectively
disenfranchised most blacks for decades. The
Equal Justice Initiative reported in 2015 that the county had 12
lynchings of African Americans from 1877 to 1950, most in the decades near the turn of the 20th century. This was the fourth-highest of any county in the state. To escape the violence, thousands of African Americans left the state in the
Great Migration to northern and western cities, especially after 1940. Mechanization of farming and industrial-scale agriculture have decreased the need for workers. The rural county has continued to lose population because of the lack of work opportunities. There has been a decrease in population every decade since 1940. ==Geography==