In 1782 the southeastern part of Burke County was annexed to Lincoln County. In 1841 parts of Lincoln County and Rutherford County were combined to form Cleveland County. In 1842 the northern third of Lincoln County became Catawba County. In 1846 the southern half of what was left of Lincoln County became Gaston County.
There were 24,041 households out of which 34.10% had children under the age of 18 living with them, 61.20% were married couples living together, 10.00% had a female householder with no husband present, and 24.40% were non-families. 20.10% of all households were made up of individuals and 7.80% had someone living alone who was 65 years of age or older. The average household size was 2.62 and the average family size was 3.00.
In the county the population was spread out with 24.90% under the age of 18, 7.70% from 18 to 24, 31.70% from 25 to 44, 24.20% from 45 to 64, and 11.50% who were 65 years of age or older. The median age was 36 years. For every 100 females there were 98.90 males. For every 100 females age 18 and over, there were 96.60 males.
The median income for a household in the county was $41,421, and the median income for a family was $47,752. Males had a median income of $32,394 versus $22,362 for females. The per capita income for the county was $18,877. About 6.90% of families and 9.20% of the population were below the poverty line, including 10.90% of those under age 18 and 14.10% of those age 65 or over.