Mendham Township is a township in southwestern Morris County, in the U.S. state of New Jersey, located more than due west of New York City. As of the 2020 United States census, the township's population was 6,016,
Located on the northern end of the Somerset Hills, Mendham Township is situated in the Raritan Valley region within the New York Metropolitan area. The township may be named for Mendham, Suffolk, England, or it may derive from the Native American word mendom (meaning "raspberry") or for an Earl of Mendham.
The long-established hamlets of Brookside and Ralston are located within Mendham, and both are listed on the National Register of Historic Places.
Along with Mendham Borough, the Mendhams have been described by The New York Times as "both affluent". The township has been one of the highest-income small municipalities in the United States.<!-- WEALTH MEASURES NET WORTH; INCOME MEASURES ANNUAL EARNINGS; THE DATA WE HAVE HERE IS FOR INCOME, NOT WEALTH.--> Based on data from the 2012-2016 American Community Survey, NJ.com ranked the township as having the third-highest income in the state, with a median household income of $176,875. Based on data from the ACS for 2014–2018, Mendham Township ranked fifth in the state with a median household income of $185,882. Per capita income, in comparison, was $131,795 as of the 2020 United States Census.
In 2010, Forbes.com listed Mendham as 224th in its listing of "America's Most Expensive ZIP Codes", with a median home price of $1,006,491.
History
The township was formed on March 29, 1749, from portions of Hanover Township, Morris Township and Roxbury Township. After the Revolutionary War, on February 21, 1798, the township was incorporated by the Township Act of 1798 of the New Jersey Legislature as one of the state's initial group of 104 townships. Portions of the township were taken to create Randolph Township on January 1, 1806. Mendham Borough became an independent municipality when it was formed on May 15, 1906.
Natural resources of water, forests and minerals drew settlers to the area. The area of Ralston had iron forges, sawmills, and a gristmill by 1748, located in an area along the North Branch of the Raritan River. Northeast of Ralston is India Brook. On the eastern side of Mendham Township, brooks that formed the upper reaches of the Whippany River attracted settlers to the valley called Water Street or Waterville, later known as Brookside.
Following the Civil War, wealthy industrialists and financiers established country homes in the Morristown area and Bernardsville's "Mountain Colony", including in the Mendhams. Historic homes, structures, and local settlements are relics of the township's history as a community where people lived and worked in a rural community far from the city's "dark satanic mills".
Geography
According to the United States Census Bureau, the township had a total area of 18.01 square miles (46.65 km<sup>2</sup>), including 17.78 square miles (46.06 km<sup>2</sup>) of land and 0.23 square miles (0.59 km<sup>2</sup>) of water (1.27%).
The long-established hamlets of Brookside and Ralston are located within the township and both are listed among the National Register of Historic Places.
The township surrounds Mendham Borough on three sides and borders Morris Township to the east, Harding Township to the southeast, Randolph to the north and Chester Township to the west all of which are located in Morris County; Bernardsville lies to the south and Peapack-Gladstone lies to the southwest, both located in the Somerset Hills of Somerset County.