The first permanent European settlement on Delaware soil was Fort Christina, resulting from Peter Minuit's 1638 expedition on the Swedish vessels Fogel Grip and Kalmar Nyckel.

They contracted with the Lenape Native Americans for land of Old Cape Henlopen north to Sankikans (Trenton Falls), and inland as far as they desired.

Printz settled on Tinicum Island, as the seat of government and capital of the New Sweden colony.

Having learned of the fall of Fort Casimir, the Dutch sent Stuyvesant to drive the Swedes from both sides of the river.

They allowed only Dutch colonists to settle in the area and on August 31, 1655, the territory was converted back to Fort Casimir.

John Paul Jacquet was immediately appointed governor, making New Amstel the capital of the Dutch-controlled colony.

On December 22, 1663, the Dutch transferred property rights to the territory along the Delaware River to England.

One of the first acts by the Duke was to order removal of all Dutch from New Amsterdam; he renamed New Amstel as New Castle.

On September 12, 1673, the Dutch established New Amstel in present-day Delaware, fairly coterminous with today's New Castle County.

In 1681, a 12-mile arc was drawn to specifically delineate the northern border of New Castle County as it currently exists.

In 1685, the western border was finally established by King James II; this was set as a line from Old Cape Henlopen (presently Fenwick) west to the middle of the peninsula and north up to the middle of the peninsula to the 40th parallel.

New Castle County is apportioned into eleven hundreds: Brandywine, Christiana, Wilmington (the city of Wilmington, which, by law, is a hundred in itself), Mill Creek, White Clay Creek, Pencader, New Castle, Red Lion, St. Georges, Appoquinimink, and Blackbird.

Ebright Azimuth, the highest natural point in Delaware at 448 feet (137 m), is located in New Castle County.

[24] The council is tasked with drafting laws and managing county government services, public health ordinances, land use, transportation, and zoning.

Its most famous council member was Joe Biden, the 46th president of the United States, who represented the 4th district from 1971 to 1973.

These courts have jurisdiction over driving offenses, misdemeanor criminal charges, and minor civil claims.

In Delaware, these offices are clerk of the peace, recorder of deeds, register of wills, and sheriff.

The office of clerk of the peace is unique among the 50 states; the office-holder's function is almost exclusively to perform marriages.

His office receives and records wills and small-estate affidavits upon an individual's death, and issues letters of administration to estate executors.

The civil division serves legal process, performs levies & impounds and sells property in satisfaction of judgments.

The UDC was developed by the Gordon Administration in response to public perception of over- and misdevelopment in the county.

By operation of state law, New Castle County has no responsibility whatsoever for maintenance of roadways.

The Department of Public Works maintains essential infrastructure elements such as sanitary sewers and drainage ways.

The city of Wilmington has its own career municipal fire department and contracts with a private ambulance service for basic life support coverage.

The contracted private ambulance service in Wilmington operates in a tiered response configuration with the New Castle County Paramedics.

The Paul J. Sweeney Public Safety Building, located in Minquadale off of US 13, houses the New Castle County Police and Emergency Medical Services Division Headquarters and the emergency communications center supporting 9-1-1 services.

In 1992, 2000, 2004 and 2016, the Republican candidate carried Kent and Sussex, only to lose New Castle by double digits–enough of a margin to swing the entire state to the Democrats.

It became the longest-running national bellwether after 1996, when Okanogan County, Washington, voted for Bob Dole.

Former governor Ronald Reagan won the county by just one vote over President Jimmy Carter in 1980.

[38] The Howard R. Young Correctional Institution, renamed from Multi-Purpose Criminal Justice Facility in 2004 and housing both pretrial and posttrial male prisoners, is located in Wilmington; it opened in 1982.