Mississippi County, Arkansas: History
=== Pre-European exploration ===
Extant early settlements include the Eaker Site and the Sherman Mound.
Local oral tradition held that prior to the major earthquakes of 1812, the lands in Mississippi County were higher in elevation compared to now and were not prone to flooding. Though the earthquake was named for New Madrid, Missouri, as that was the only town in the area with any population, the actual epicenter of the quake was three miles below what is now Blytheville, Arkansas.
American settlers were recorded in the area as early as 1828. These early settlers include John Troy, the first Mississippi County Judge and namesake of Troy township and G.C. Barfield, the first county surveyor and namesake of Barfield Landing.
Mississippi County was created on November 1, 1833, when it was split off from Craighead County. By 1836, when Arkansas achieved statehood, the county's white population had slightly increased and the local Native population was pushed in the eastern part of the county, towards what is now Big Lake. The first county seat was a small community called Cornwall, which was located on the banks of the Mississippi River, on the remains of an old Spanish "encampment." Osceola was named as the County Seat in 1833, and later incorporated in 1843.
The Federal Swamp Act of 1850 granted federally controlled swamp lands to their respective state governments for sale. According to the 1852 surveyor general's report, Mississippi County had the largest amount of swamp and "Sunken" lands of any county in the country.
Following the American Civil War, Mississippi County was one of 10 counties in Arkansas put under martial law due to increased activity from the Ku Klux Klan. In 1872, a series of racial and political confrontations known as the Black Hawk War took place. The genesis of this was the murder of "Carpetbagger" Charles Fitzpatrick by the county Sheriff J.B. Murray over Fitzpatrick's allegations of Murray's embezzlement of school funds.
During World War II, a B-25 pilot training school was constructed at Blytheville, with satellite landing strips at Manilla and in the Missouri Bootheel. The facility was later reopened in 1954 at Blytheville Air Force Base, and hosted a squadron of B-52s from 1959 to 1992.
In 1987, Nucor Steel opened a steel plant at Barfield Landing on the Mississippi River. In 2014, U.S. Steel opened a steel plant at Osceola. Mississippi County is now reportedly the largest steel producing county in America.