Raritan is a borough in Somerset County, New Jersey, United States. As of the 2010 United States Census, the borough's population was 6,881, reflecting an increase of 543 (+8.6%) from the 6,338 counted in the 2000 Census, which had in turn increased by 540 (+9.3%) from the 5,798 counted in the 1990 Census.
The township's name is derived from the Raritans, a Native American group of Lenapes. The name of the tribe is said to mean "forked river", "stream overflows" or "point on a tidal river".
Raritan town was originally established as a subdivision within Bridgewater Township by act of the New Jersey Legislature on April 3, 1868. After a series of bitter lawsuits between Raritan and Bridgewater in the 1930s and 1940s, the Legislature allowed Raritan to become a fully independent Borough by an Act on May 12, 1948, based on the results of a referendum passed on June 12, 1948. The new borough incorporated the old town and an additional portion of Bridgewater Township.
The Knox–Porter Resolution ending United States involvement in World War I was signed by President Harding at the estate of New Jersey Senator Joseph S. Frelinghuysen Sr. on July 2, 1921.
According to the United States Census Bureau, the borough had a total area of 2.037 square miles (5.276 km2), including 1.993 square miles (5.162 km2) of land and 0.044 square miles (0.114 km2) of water (2.15%).
The borough borders Bridgewater Township, Hillsborough Township and Somerville.
Raritan is in the western division of the Raritan Valley (a line of cities in central New Jersey), along with Branchburg and Bridgewater.
As of the 2010 United States Census, there were 6,881 people, 2,673 households, and 1,748.142 families residing in the borough. The population density was 3,452.2 per square mile (1,332.9/km2). There were 2,847 housing units at an average density of 1,428.3 per square mile (551.5/km2). The racial makeup of the borough was 76.40% (5,257) White, 2.09% (144) Black or African American, 0.16% (11) Native American, 14.29% (983) Asian, 0.01% (1) Pacific Islander, 4.59% (316) from other races, and 2.46% (169) from two or more races.