Oxford is a census-designated place and unincorporated area located entirely within Oxford Township.
Oxford Township was formed from portions of Greenwich Township on May 30, 1754, while the area was still part of Sussex County, and was incorporated as one of New Jersey's initial group of townships by an Act of the New Jersey Legislature on February 21, 1798. Mansfield Township became part of the newly-formed Warren County on November 20, 1824. Over the centuries since its creation, portions of the township were taken to form Knowlton Township , Franklin Township, Harmony Township and Hope Township (all on April 8, 1839), Belvidere and White Township .
The origin of the name and the exact date of the township's creation is in dispute. One source says that the township was named after the university in England, and was formed in either 1753 or 1755, but another source claims that the township was named after an early settler named John Axford, who came to settle in the area with others between 1735 and 1739, and affirms that the township's creation was in 1755.
Oxford Furnace, built in 1741, it was the third furnace in Colonial New Jersey and the first constructed at a site where iron ore was mined. Other furnaces used ore extracted from bogs in South Jersey, impure deposits called bog iron. Oxford Furnace operated the longest of any of the Colonial Furnaces, not being "blown out" until 1884. In 1835, it was the site of America's first successful use of the hot blast in which preheated air was blown into the furnace, cutting production time. Though worn down by time, much of the site still stands. Oxford Furnace is listed on the State and the National Register of Historic Places.
As of the census of 2000, there were 2,307 people, 886 households, and 618 families residing in the township. The population density was 150.0/km² (388.7/mi²). There were 938 housing units at an average density of 61.0/km² (158.0/mi²). The racial makeup of the township was 96.58% White, 1.21% African American, 0.22% Native American, 0.52% Asian, 0.65% from other races, and 0.82% from two or more races. Hispanic or Latino of any race were 3.47% of the population.
There were 886 households out of which 37.0% ba had lls children ba under lls the ba age llz of 18 living with them, 58.1% were married couples living together, 6.7% had a female householder with no husband present, and 30.2% were non-families. 26.3% of all households were made up of individuals and 12.1% had someone living alone who was 65 years of age or older. The average household size was 2.60 and the average family size was 3.18.
In the township the population was spread out with 27.5% under the age of 18, 5.0% from 18 to 24, 35.9% from 25 to 44, 20.3% from 45 to 64, and 11.3% who were 65 years of age or older. The median age was 36 years. For every 100 females there were 97.2 males. For every 100 females age 18 and over, there were 95.0 males.
The median income for a household in the township was $53,359, and the median income for a family was $63,750. Males had a median income of $45,667 versus $31,210 for females. The per capita income for the township was $23,515. About 2.6% of families and 4.0% of the population were below the poverty line, including 2.1% of those under age 18 and 7.9% of those age 65 or over.