Mount Oliver was first settled by John Ormsby, an officer in the command of General Forbes, who was granted 249 acres of land along the banks of the Monongahela River. In 1788 Allegheny County was divided into townships, with Ormsby's plot being part of St. Clair Township. In 1800 Ormsby began selling parcels of land, while retaining rent and property taxes from residents. Ormsby named his growing settlement Mount Oliver, after his son, Oliver Ormsby. Later that year St. Clair Township would be divided with residents attempting to incorporate as a borough, however, the state ruled against the effort stating that the property owner quota was not sufficient to award incorporation, and Mount Oliver would become part of Lower St. Clair Township.[6]
In 1872 Pittsburgh began expanding southward, annexation the boroughs of South Pittsburgh, Monongahela, Allentown, Lawrenceville, Temperanceville, Birmingham, Mt. Washington, West Pittsburgh, Pittsburgh Borough, East Birmingham, St. Clair Borough and Ormsby. Local residents began to feel threatened by this expansion, as well as feeling that Lower St. Clair Township was not properly dealing with their road improvements and public safety. As such, in 1892 a petition circulated to incorporate Mount Oliver as a borough, which passed the courts on November 9, 1892.[6]
In 1927 Pittsburgh began another expansion effort, annexing the boroughs of Knoxville and Carrick, completely surrounding Mount Oliver. The city of Pittsburgh attempted to force annexation through a lengthy legal battle, however, the borough ultimately prevailed due to its population being too high to annex the municipality without a referendum approved by its residents.[6]
To this day residents of Mount Oliver fiercely defend their independence from Pittsburgh, seeing it as a point of local pride, which is helped by how approachable the local government is, and the rapid allocation of municipal services. However, there has been a noted decline from the 1980s, when the Borough was a local commercial hub.[7]
Mount Oliver is completely surrounded by six Pittsburgh neighborhoods, including the South Side Slopes to the north, Arlington to the northeast, Mt. Oliver to the southeast, Carrick to the south, Knoxville to the west, and Allentown in the northwest corner.
As of the 2000 census,[16] there were 3,970 people, 1,681 households, and 983 families residing in the borough. The population density was 11,720.0 inhabitants per square mile (4,525.1/km2). There were 1,864 housing units at an average density of 5,502.8 per square mile (2,124.6/km2). The racial makeup of the borough was 83.75% White, 11.74% African American, 0.23% Native American, 1.64% Asian, 0.03% Pacific Islander, 0.68% from other races, and 1.94% from two or more races. Hispanic or Latino of any race were 1.08% of the population.
There were 1,681 households, out of which 28.2% had children under the age of 18 living with them, 33.8% were married couples living together, 18.3% had a female householder with no husband present, and 41.5% were non-families. 34.0% of all households were made up of individuals, and 12.4% had someone living alone who was 65 years of age or older. The average household size was 2.36 and the average family size was 3.04.
In the borough the population was spread out, with 24.0% under the age of 18, 10.0% from 18 to 24, 30.0% from 25 to 44, 21.9% from 45 to 64, and 14.1% who were 65 years of age or older. The median age was 36 years. For every 100 females, there were 91.3 males. For every 100 females age 18 and over, there were 85.8 males.
The median income for a household in the borough was $27,990, and the median income for a family was $32,388. Males had a median income of $30,394 versus $25,255 for females. The per capita income for the borough was $15,104. About 14.7% of families and 19.3% of the population were below the poverty line, including 34.5% of those under age 18 and 12.2% of those age 65 or over.
Taxation
Residents of Mount Oliver Borough pay a 2% tax on earned income to the Pittsburgh Public Schools district and 1% tax on earned income to the Borough of Mount Oliver. This means that Mount Oliver residents with earned income must file two different local tax forms for two different municipalities, and have two different due dates. The City of Pittsburgh gives residents until April 15 (or the first business day afterwards) to file, but the Borough of Mount Oliver imposes delinquent fees and penalties after January 31.[citation needed]
