Florence County was formed from main sections of Darlington and Marion Counties plus other townships from Williamsburg and Clarendon Counties, starting in 1888. The last section of Williamsburg County was not added until 1921. Florence County was named for the daughter of General W. W. Harlee.
Geography
According to the U.S. Census Bureau, the county has a total area of, of which is land and is water.
At the 2000 census there were 125,761 people, 47,147 households, and 33,804 families living in the county. The population density was 157 people per square mile. There were 51,836 housing units at an average density of 65 per square mile. The racial makeup of the county was 58.65% White, 39.34% Black or African American, 0.22% Native American, 0.70% Asian, 0.02% Pacific Islander, 0.39% from other races, and 0.68% from two or more races. 1.10% of the population were Hispanic or Latino of any race. Of the 47,147 households 33.80% had children under the age of 18 living with them, 49.70% were married couplesliving together, 18.10% had a female householder with no husband present, and 28.30% were non-families. 24.50% of households were one person and 8.20% were one person aged 65 or older. The average household size was 2.59 and the average family size was 3.08. The age distribution was 25.90% under the age of 18, 9.70% from 18 to 24, 28.90% from 25 to 44, 23.60% from 45 to 64, and 11.80% 65 or older. The median age was 36 years. For every 100 females, there were 88.70 males. For every 100 females age 18 and over, there were 84.20 males. The median household income was $35,144 and the median family income was $41,274. Males had a median income of $32,065 versus $21,906 for females. The per capita income for the county was $17,876. About 13.50% of families and 16.40% of the population were below the poverty line, including 22.30% of those under age 18 and 16.50% of those age 65 or over. In census 2000, the population of Florence County was classified as 58% urban and 42% rural, containing the two urban areas of Florence and Lake City. Along with Darlington County, it comprises part of the Florence Metropolitan Statistical Area.
2010 census
At the 2010 census, there were 136,885 people, 52,653 households, and 36,328 families living in the county. The population density was. There were 58,666 housing units at an average density of. The racial makeup of the county was 54.9% white, 41.3% black or African American, 1.2% Asian, 0.3% American Indian, 1.1% from other races, and 1.1% from two or more races. Those of Hispanic or Latino origin made up 2.2% of the population. In terms of ancestry, 8.4% were American, 7.8% were English, 6.7% were Irish, and 6.2% were German. Of the 52,653 households, 35.2% had children under the age of 18 living with them, 44.7% were married couples living together, 19.6% had a female householder with no husband present, 31.0% were non-families, and 26.3% of households were made up of individuals. The average household size was 2.54 and the average family size was 3.06. The median age was 37.6 years. The median household income was $40,487 and the median family income was $48,896. Males had a median income of $38,934 versus $30,163 for females. The per capita income for the county was $21,932. About 14.5% of families and 18.0% of the population were below the poverty line, including 26.1% of those under age 18 and 14.0% of those age 65 or over.
