The United States acquired the area of Arkansas from France as part of the Louisiana Purchase in 1803. Arkansas Territory (spelled in the enabling act as Arkansaw) was organized from part of Missouri Territory on March 2, 1819, and included the greater part of Oklahoma, west to the 100th meridian. Arkansas Territory was reduced in area in 1824 and 1828 to generally assume the boundary of the present state. Arkansas was admitted to the Union on June 15, 1836, as the 25^th state.

Although the territory had not yet been established, census data are available for Arkansas beginning with the 1810 census (as part of Louisiana Territory). The 1810 and 1820 populations for Arkansas reflect the 1819 boundary of the territory, which included territory now in the state of Oklahoma. The population of the entire legally established Louisiana Territory (of which the area of Arkansas was a part) in 1810 was 20,845.

Data for the legally established state of Arkansas are available beginning with the 1840 census.

METROPOLITAN AND MICROPOLITAN STATISTICAL AREAS AND RELATED STATISTICAL AREAS

Arkansas has 8 metropolitan statistical areas, 14 micropolitan statistical areas, and 2 combined statistical areas.

COUNTIES

There are 75 counties in Arkansas.  The governing body for each county consists of justices of the peace and a county judge.

COUNTY SUBDIVISIONS

There are 1,271 county subdivisions in Arkansas.  There are 1,270 townships which are recognized as minor civil divisions (MCDs).  Fort Chaffee in Sebastian County is an unorganized territory. All county subdivisions in Arkansas are nonfunctioning, nongovernmental entities.

PLACES

Arkansas has 541 places; 502 incorporated places and 39 census designated places (CDPs).  The incorporated places consist of 311 cities (minimum population threshold of 500) and 191 towns (population less than 500).  One town and four cities are each coextensive with a single township with the same name. 

CENSUS TRACTS/BLOCK GROUPS/BLOCKS

Arkansas has 686 census tracts, 2,147 block groups, and 186,211 census blocks.

CONGRESSIONAL DISTRICTS

For the 111^th Congress (January 2009-January 2011), Arkansas had four congressional districts.  For the 113^th Congress (January 2013-January 2015), Arkansas continues to have four congressional districts as a result of reapportionment based on the 2010 Census.

SCHOOL DISTRICTS

Arkansas has 251 unified school districts. 

STATE LEGISLATIVE DISTRICTS

There are 35 state senate districts and 100 state house districts in Arkansas.

URBAN AREAS

Arkansas has 72 urban areas; 9 urbanized areas and 63 urban clusters.

ZIP CODE TABULATION AREAS

There are 596 ZIP Code tabulation areas (ZCTAs) in Arkansas.

¹  Source:  U.S. Department of Commerce, Bureau of the Census, Fourteenth Census of the United States, 1923
²  Source:  U.S. Census Bureau, recomputation for historical county level data which relied upon aggregate county level population data with an estimated county centroid resulting in a possible error of up to one mile.
³  Source:  U.S. Department of Commerce, Bureau of the Census, Centers of Population for States and Counties, 1974
⁴  Source:  U.S. Census Bureau, Geography Division, recomputation from archived national block group/enumeration area data resulting in a possible error of up to 1,000 feet.
⁵  Source:  U.S. Census Bureau, Geography Division, recomputation from archived national block group data resulting in a possible error of up to 1,000 feet.
⁶  Source:  U.S. Census Bureau, computation from national block-level data