Roselle Park is a borough in Union County, New Jersey, United States. As of the 2010 United States Census, the borough's population was 13,297, reflecting an increase of 16 (+0.1%) from the 13,281 counted in the 2000 Census, which had in turn increased by 476 (+3.7%) from the 12,805 counted in the 1990 Census.
Roselle Park was incorporated as a borough by an act of the New Jersey Legislature on March 22, 1901, from portions of Union Township. Roselle Park's name is derived from the Roselle Land Improvement Company, which was created in 1866 to lay out a community around the Mulford Station on the Central Railroad of New Jersey. The name "Roselle" is said to have been based on the company's founder, John Conklin Rose or from John Pierre Roselle, a friend of the railroad's president.
The first known settlement within what is now the Borough was built by Samuel Williams in 1700. Galloping Hill Road was continually used by revolutionary war scouts, delivering messages to and from General George Washington and Governor Livingston. Galloping Hill Road also believed to be the route traveled by the British columns en route to the Battle of Connecticut Farms, battling the New Jersey militia the entire way. Son of American general William Crane, was bayoneted and killed by the British near what is now Galloping Hill Road and Colonial Road.
Elizabethtown & Somerville Railroad passed through in 1839, as the first railroad in Northern New Jersey. The first store in the world to be lit by electric light was Stone's Store on Westfield Avenue, lit by Thomas Edison's carbon filament prototype.
The formation of Roselle Park in 1901 occurred due to a number of grievances based on a lack of sufficient public services, including; lack of a modern sewage system, poor schools, neglected roads, and minimal public safety measures.
In 1907, the first poured concrete building in the world, now the Robert Gordon School, was built in Roselle Park using Edison's revolutionary process. Roselle Park was home to the factory and lab of Marconi Wireless Telegraph, and in late 1921 became the site of WDY, the first radio broadcasting station licensed in the state of New Jersey.
According to the United States Census Bureau, the borough had a total area of 1.23 square miles (3.17 km2), all of which was land.
Unincorporated communities, localities and place names located partially or completely within the borough include Lorraine.
The borough is bordered to the northeast by Union Township, to the northwest by Kenilworth, to the east by Elizabeth, to the south by Roselle and to the west by Cranford.
The 2010 United States Census counted 13,297 people, 5,002 households, and 3,406 families in the borough. The population density was 10,792.7 inhabitants per square mile (4,167.1/km2).