The settlement history of the Upper Delaware is long and varied, marked by changing climate and economic conditions. Native American populations may have lived along the banks of the Upper Delaware as early as 15,000 B.C., although it is likely that continued habitation may not have occurred until 6,000 B.C. or later. The Woodland Indian culture, dating from 1,000 B.C., was the first to practice agriculture. They gave way to the Minsi Indian culture, the group first encountered by Dutch traders as early as about 1614 A.D.
Swedish settlers were reported to have made their way as far north as Cochecton by 1630, but more substantial settlements did not spring up until the 1730s. That group of people known as Connecticut Yankees and a few Dutch settlers were the main arrivals to the area during the late 18th and early 19th centuries. They were followed by the Irish, who helped build the D & H Canal and Erie Railroad, and by the Germans, who came to farm the land. The typical new arrival during the 20th century has been the urban resident looking for green space and a better quality of life.
Economically, the area has ridden the waves of transportation development and the extraction of natural resources. The construction of the Newburgh-Cochecton Turnpike around 1800 was the first of the main roads to traverse the area. It was followed by the Delaware & Hudson Canal, completed in 1828. The Erie Railroad began operations through the Upper Delaware Valley in 1851, and the final major transportation route, New York Highway 97, was completed in 1940.
Timber rafting began in the 1760s, developing into a focal point of the local economy after the Revolution. During the peak years in the mid-19th century, over 50 million board feet of pine and hemlock were shipped down river annually. It was not until the early 20th century, when easily marketable forests had been logged, that the industry declined and died. From the 1850s until the 1880s, tanneries were major industries in the valley, but they ceased to operate after the hemlock groves they used to obtain tannin were largely cut over. Quarrying operations took the place of the tanneries, and rock such as bluestone was shipped in large quantities to places such as New York City and Jersey City for streets and curbs. The industry has changed, but it is still viable.
Agricultural land is an important economic resource within the river corridor. Historically, agriculture played a large role in the settlement and economic development of the river corridor, but in recent decades much of the farmland has returned to forested condition. Areas of fertile, well-drained silt and sandy loam soils support good crop land and pasture land. dairy and field crops are important elements of farm production in the river valley.