Millville was originally incorporated as a township by an act of the New Jersey Legislature on February 24, 1801, from portions of Fairfield Township. Portions of the township were taken to form Landis Township on March 7, 1864. Millville was reincorporated as a city on March 1, 1866, based on the results of a referendum passed that same day. The city derives its name from a proposal to create a mill town in the area.
In 1790, Joseph Smith and Henry Drinker purchased 24,000 acres (97 km2) of land known as the Union Mills Tract. They formed the Union Estates Company, built lumber mills along the Maurice River and established a dam to power these new mills. Joseph Buck, an American Revolutionary War veteran who served under General George Washington, was part of a group that purchased the land in the area in 1795 and laid out the plans for what would become Millville.
In 1806, an Irish immigrant, James Lee, opened the area's first glass factory, making use of the large amounts of silica sand and the ample wood that could be used to operate the plant.
In the early 1850s, the Smith and Wood Iron Foundry and New Jersey Mills were constructed. In 1860, a bleachery and dye house were added to New Jersey Mills, which then became Millville Manufacturing. David Wood then constructed a dam, forming the largest man-made lake in the state, which powered the entire manufacturing organization. By 1870, the mill had 600 employees, and in 40 years this number doubled.