[19] Stillwater was settled in the eighteenth century by Palatine German immigrants who entered through the port of Philadelphia.

In 1741, Casper Shafer, John George Wintermute (Windemuth), and their father-in-law Johan Peter Bernhardt settled along the Paulins Kill.

[21] The German population assimilated by the early nineteenth century, but evidence of their settlement remains in the architecture of the grist mills, lime kilns, and stone houses located throughout the valley.

[20] Stillwater was incorporated as a township by an act of the New Jersey Legislature on December 27, 1824, from portions of Hardwick Township[22][23] when Sussex County was divided in half by the legislature a few weeks earlier to create Warren County.

Originally built by Casper Shafer in 1741, it was moved approximately a half mile to its present location in 1764.

Casper's son, Nathan Armstrong Shafer lived in Whitehall Manor, which he built near what is now the center of the village.

[citation needed] Opposite the church is the former Academy, an old schoolhouse that is now home of the Historical Society of Stillwater Township.

An intact kiln still exists on Millbrook Road, a little more than two miles (3 km) from Stillwater village.

Stillwater is a small one-street village in the area that was first settled by Johan Peter Bernhardt and his two sons-in-law, John George Wintermute and Casper Shafer.

At the western terminus of end of Main Street where it meets County Route 521, the First Presbyterian Church of Stillwater is the dominant feature.

Located adjacent is Stillwater Cemetery—the site of the original Lutheran-Calvinist union church (1771–1838), the graves of the towns earliest settlers, and many eighteenth century ethnic German gravestones.

[42] According to Snell, "The surface of the country is generally uneven and hilly, and on the west exceedingly rugged and mountainous.

"[43] All of Stillwater Township is located in the Paulins Kill watershed which flows southwest through Sussex and Warren counties before joining the Delaware River near Columbia, New Jersey.

The 2010 United States census counted 4,099 people, 1,553 households, and 1,141 families in the township.

[56] As of the 2000 United States census[14] there were 4,267 people, 1,494 households, and 1,154 families residing in the township.

[64] The Stillwater Area Volunteer Fire Company provide fire and rescue services to the township[65] Stillwater station houses CAFS Pumper 42–62, Rescue-Pumper 42–61, Tanker/Pumper 42–71, Tanker 42–72, Rescue 42–75 and utility and special operations 42–81.

In February 2016, the township disbanded the Swartswood Volunteer Fire Department and reclaimed township-owned vehicles and other property.

The Fire Department now provides emergency medical services to the township, utilizing two full-size ambulances.

[68][69][70] For the 119th United States Congress, New Jersey's 7th congressional district is represented by Thomas Kean Jr. (R, Westfield).

[72] For the 2024-2025 session, the 24th legislative district of the New Jersey Legislature is represented in the State Senate by Parker Space (R, Wantage Township) and in the General Assembly by Dawn Fantasia (R, Franklin) and Mike Inganamort (R, Chester Township).

At an annual reorganization meeting held in the beginning of January, the board selects a Commissioner Director and Deputy Director from among its members, with day-to-day supervision of the operation of the county delegated to a County Administrator.

[84] Among the township's 2010 Census population, 73.4% (vs. 65.8% in Sussex County) were registered to vote, including 94.0% of those ages 18 and over (vs. 86.5% countywide).

[99] The high school is located on a 96-acre (39 ha) campus in Hampton Township, about seven minutes outside of the county seat of Newton.

[103] People who were born in, residents of, or otherwise closely associated with Stillwater Township include: