Blairsville was settled in 1818 and incorporated in 1825. In the past, railway shops, foundries, machine shops, enameling plants, and manufactories of plate glass and lumber employed the residents. It was the seat of Blairsville College, a Presbyterian institution opened in 1851. Just outside of the city limits in Burrell Township, the former auto repair trade school Wyotech, operated until 2018. The Blairsville Armory and St. Peter's Episcopal Church and Rectory are listed on the National Register of Historic Places. In 1902, the countryside around Blairsville became one of the first in Pennsylvania to have a woman, Anna J. Devers, appointed as a Rural Free Delivery carrier, delivering mail from the Blairsville Post Office. M. C. Eignus, Illinois state representative, was born in Blairsville.
At the 2000 census there were 3,607 people, 1,631 households, and 983 families residing in the borough. The population density was 2,591.3 people per square mile. There were 1,830 housing units at an average density of 1,314.7 per square mile. The racial makeup of the borough was 95.68% White, 2.99% African American, 0.11% Native American, 0.58% Asian, 0.06% from other races, and 0.58% from two or more races. Hispanic or Latino of any race were 0.06%. There were 1,631 households, 25.4% had children under the age of 18 living with them, 46.8% were married couplesliving together, 10.1% had a female householder with no husband present, and 39.7% were non-families. 36.3% of households were made up of individuals, and 19.1% were one person aged 65 or older. The average household size was 2.21 and the average family size was 2.90. In the borough the population was spread out, with 22.4% under the age of 18, 6.5% from 18 to 24, 27.3% from 25 to 44, 22.7% from 45 to 64, and 21.2% 65 or older. The median age was 41 years. For every 100 females there were 88.8 males. For every 100 females age 18 and over, there were 85.2 males. The median household income was $30,625 and the median family income was $38,585. Males had a median income of $32,563 versus $22,049 for females. The per capita income for the borough was $16,771. About 6.8% of families and 11.2% of the population were below the poverty line, including 15.7% of those under age 18 and 9.9% of those age 65 or over.
