Long Hill Township was incorporated as Passaic Township on March 23, 1866. On September 1, 1922, part of what was then Passaic Township was taken to form Harding Township. On November 3, 1992, by a 1,901–1,821 margin, the voters elected to change the name of the municipality to Long Hill Township, a change largely driven by the desire to avoid confusion with the City of Passaic, some 22 miles (35 km) away.
Garden State Fireworks, a firm based in Millington that dates back to 1890, has produced the annual July 4 fireworks show in Washington, D.C. on the National Mall. The Raptor Trust is a wild bird rehabilitation center located in Millington.
Clover Hill Swimming Club a club surrounding a lake in Millington, was the subject of lawsuit in which the Supreme Court of New Jersey ruled in 1966 that the club could not discriminate against an African American applicant for membership on the basis of the club being private.
|Routes through Long Hill|
|Peapack-Gladstone ← Basking Ridge ←||W E||→ New Providence → Summit|