[13] While there are differing historical theories, the most plausible of theories in the origin of the county's name are attributed to many settlers originating from Rhode Island where the Rhode Island Monmouth Society hailed from, or it being named after the historic county of Monmouthshire in Wales, Great Britain.

Located in the middle of the Northeast megalopolis, its inland county seat of Freehold Borough, the Tri-City region of coastal cities of Red Bank, Long Branch, and Asbury Park, along with the county constituting a vast swath of the New Jersey coastline, has contributed in its draw of tourists throughout the state (and much of the Northeastern United States at large), particularly during the summer months.

The Bell Labs Complex is a major scientific research facility in Holmdel Township, where important breakthroughs, such as evidence for the Big Bang, were discovered.

Another plausible theory, is from a suggestion from Colonel Lewis Morris that the county should be named after Monmouthshire in Wales, Great Britain.

[25] Around the year 1000, the area of Monmouth County began to be inhabited by the Lenape Native Americans prior to the arrival of European settlers.

During this time, an important crossroad of two major Lenape trails was located in the area of Freehold Township in western Monmouth County.

A group of Quaker families from Long Island settled the Monmouth Tract, an early land grant from Richard Nicolls issued in 1665.

At Monmouth the tactics and training from Friedrich Wilhelm von Steuben developed at Valley Forge during the winter encampment were first implemented on a large scale.

[31] Other battles and massacres during the war in Monmouth County include sites such as the Burrowes Mansion in Matawan, and the Allen House in Shrewsbury.

[32] In 1790 Monmouth County's population was 16,918, of whom roughly 6,600 were of English descent and the remainder were Welsh, Dutch and Swedish, as well as small amounts of African Americans and Northern Irish Protestants.

[35] At the same time the region underwent massive and not unrelated economic changes, this process led to places like Monmouth County, New Jersey becoming significantly more diverse and somewhat less rural.

On August 7, 1874, the Sandy Hook Proving Ground was established as a weapons testing area, considered a separate facility from the fort.

[38] During the 19th century, Keyport's Marine Park was a major shipbuilding hub, having built 55 steamships between 1807 and 1868, which was more than Hoboken, Jersey City, or Camden during this period.

[40] On September 19, 1881, U.S. President James A. Garfield died in the Elberon section of Long Branch, a few months after being shot in a failed assassination attempt.

In 2004, the building was deemed unsafe, and was ordered to be demolished, although various elements were saved such as the iconic Tillie mural and the carousel.

[43] In 1910, the Wright Brothers hosted an aviation show in Interlaken, where numerous records were broken, such as high altitudes, longest time airborne, the first night flight, and the first air mail delivery.

Many well-known acts had performed at the theater, such as Tony Bennett, Olivia Newton-John, Bruce Springsteen, and Jon Bon Jovi.

[48] On September 8, 1934, the SS Morro Castle caught fire and burned during a storm on its route from New York City to Havana, Cuba.

[49] On December 13, 1943, Naval Weapons Station Earle was commissioned, which is designed to safely store and transport military ordinance.

In 1996, the facility expanded heavily, adding thousands in capacity, and shifting toward general music with broader appeal to compete with other amphitheaters.

The riot was largely due to high unemployment, poor housing conditions, and lack of recreational activities within the African American community.

In 2013, a developer began site redevelopment, with the research building becoming a New Urbanism inspired mixed-use facility, while the surrounding land became residential housing.

[90][91] Gramiccioni had been serving on an acting basis for almost four years, since being appointed to the post in July 2012 by Attorney General of New Jersey Jeffrey S.

[94] For the 119th United States Congress, New Jersey's 3rd congressional district is currently represented Herb Conaway (D, Delran Township).

[103] The largest volunteer department is in Middletown Township with 11 stations and 350 active members, special services, air and fire police units, in addition to operating its own training facility.

[107] The Bureau of Economic Analysis calculated that the county's gross domestic product was $34.2 billion in 2021, which was ranked ninth in the state and was a 6.1% increase from the prior year.

Some were rebuilt to a higher economic level; this process of climate gentrification is rapidly escalating property values and transforming many communities along the Shore.

[116] The Bell Labs Holmdel Complex has been the site of many innovations in telecommunications and is experiencing a renaissance as a business incubator for high-tech startup companies.

The organization remains open-admission for communities it serves, taking owner surrenders by appointment and also offers animals for adoption.

[151][152] Its Humane Law Enforcement Division investigates more than 900 animal cruelty complaints every year, and accepts anonymous calls.