The Paulins Kill was a conduit for the emigration of Palatine Germans who settled in northwestern New Jersey and northeastern Pennsylvania during the colonial period and the American Revolution.

Remnants of their chiefly agricultural settlements are still found in local architecture, cemeteries, farms and mills, and the area remains largely rural.

The Paulins Kill continues its course southwest, entering Warren County, where it initially forms the border between Frelinghuysen and Hardwick townships.

[1] After the establishment of Swartswood State Park in 1914, a dam was built in the 1920s across the river in Stillwater Township to create Paulins Kill Lake.

During the American Revolution, Hessian soldiers captured at the Battle of Trenton and other skirmishes within New Jersey were held as prisoners of war in the Stillwater area.

Local tradition does place an Indian village named Pahaquarra near the mouth of the Paulins Kill which is immediately south of the Delaware Water Gap.

[21] The first human settlement along the Paulins Kill was by early Native Americans circa 8,000–10,000 BC at the close of the last ice age (known as the Wisconsin glaciation).

Artifacts (often of stone, clay or bone) of the Native American culture are often found in nearby farm fields and at the site of their ancient villages.

[27] English, Scottish, and Welsh settlers located in the Paulins Kill valley throughout the latter half of the eighteenth century, often traveled north from Philadelphia, or west from Long Island, Newark, and Elizabethtown (now Elizabeth).

[28][29][30][31] The area around present-day Stillwater was first settled by the family of Casper Shafer (1712–1784), a Palatine German who had emigrated to Philadelphia a few years earlier.

[32][33] Shafer, who operated a grist mill at Stillwater starting in 1746, transported flour, fruit, and other products by flatboat down the Paulins Kill and the Delaware River to the market in Philadelphia.

Thomson, who removed to Changewater in Hunterdon County, became an officer in the Continental Army during the American Revolution, and served two terms in the House of Representatives.

[29] Chiefly a pastoral river in a largely undeveloped area of New Jersey, the Paulins Kill has remained generally unaffected by industrial pollution.

Several farms along the banks of the Paulins Kill produce alfalfa, wheat, corn, hay (and historically, barley, buckwheat and rye).

Fruit trees in orchards produce cherries, apples, plums, peaches and pears, while native wild grape vines, and blackberry bushes are also found in the valley.

[36][failed verification] New Jersey's Department of Environmental Protection occasionally brings civil actions against local firms that pollute in the Paulins Kill watershed, such as a $121,500 fine for a Sussex County shopping mall sewage treatment facility which discharged pollutants into a tributary of the Paulins Kill between 1996 and 1998.

[38] The New Jersey Public Interest Research Group (NJPIRG) has ranked the Paulins Kill as the seventh in a collection of rivers and creeks in a Top 30 listing of New Jersey waterways to Save[39] The Paulins Kill is home to a wide variety of amphibians, including the spotted salamander, red-spotted newt, American toad, Fowler's toad, American bullfrog and others.

[40] In 2000, a public sewer and water project in Branchville, New Jersey, was suspended out of concern for dwarf wedgemussels (Alasmidonta heterodon), an endangered species, and restarted in 2002.

[53][54][55] In addition to these state forests, the Paulins Kill valley is host to a variety of common coniferous and deciduous trees, which have been harvested for lumber in the past, including: white oak and black oak, buttonwood, eastern red cedar, eastern hemlock, American chestnut, black walnut, tamarack larch, spruce, and pine.

[56] New Jersey's Green Acres program has targeted the Paulins Kill and its surrounding valley as an excellent natural resources for open space and farmland preservation and recreational opportunities.

Common game birds include ring-necked pheasant, eastern wild turkey, American crow, and Canada goose.

[63] The Paulinskill Valley Trail—a network of rail trails along abandoned railroad beds of the New York, Susquehanna and Western Railroad—have been transformed and maintained for hiking, horseback riding, and other recreational uses, stretches for 27 miles (43 km) from Sparta Junction in Sussex County to Columbia in Warren County, roughly following the entire length of the river.

Often sighted are water fowl such as the mute swan, the wood duck, and the mallard, wading birds such as the killdeer, and predators such as the red-tailed hawk.

More rare birds sighted in the Paulins Kill valley include: purple martin, scarlet tanager, indigo bunting, Baltimore oriole, purple finch, and a variety of owls, notably the barn, eastern screech, great horned, snowy, barred, and northern saw-whet owl.