Millstone is a borough in Somerset County, New Jersey, United States. It was originally known as Somerset Courthouse and was the county seat. As of the 2010 United States Census, the borough’s population was 418, reflecting an increase of 8 (+2.0%) from the 410 counted in the 2000 Census, which had in turn declined by 40 (-8.9%) from the 450 counted in the 1990 Census.

Millstone was incorporated as a borough by an act of the New Jersey Legislature on May 14, 1894, from portions of Hillsborough Township, based on the results of a referendum held that day. The borough was reincorporated on March 12, 1928. The borough was named for the Millstone River, whose name derives from an incident in which a millstone was dropped into it.

Millstone Borough was added to the National Register of Historic Places in 1976 and encompasses 58 buildings. The borough possesses a military significance for 1700–1749, 1750–1799, 1850–1874.

Millstone, then called Somerset Courthouse, was the county seat of Somerset County from 1738 until the British burned it to the ground in 1779 during the American Revolutionary War. After the victory at Princeton on January 3, 1777, General George Washington headquartered at the Van Doren house, while the army camped nearby that night. The next day, they marched to Pluckemin on the way to their winter encampment at Morristown.

As of the 2010 United States Census, there were 418 people, 162 households, and 117.936 families residing in the borough. The population density was 566.5 per square mile (218.7/km²). There were 167 housing units at an average density of 226.3 per square mile (87.4/km²). The racial makeup of the borough was 95.69% (400) White, 1.20% (5) Black or African American, 0.00% (0) Native American, 1.67% (7) Asian, 0.00% (0) Pacific Islander, 0.96% (4) from other races, and 0.48% (2) from two or more races. Hispanic or Latino of any race were 3.59% (15) of the population.

Source: Wikipedia