New Castle County
New Castle County is the northernmost and most populous of Delaware's three counties, serving as the political, commercial, and cultural center of the state. Home to Wilmington, Delaware's largest city, the county encompasses a broad stretch of the Delaware Valley and shares borders with Pennsylvania to the north and Maryland to the west. Its long history—stretching from early European settlement through industrial growth and into the modern era—has shaped not only Delaware but the broader mid-Atlantic region. The county seat was moved from the historic city of New Castle to Wilmington in 1881, a shift that reflected the rising economic dominance of Wilmington as a center of industry and commerce.[1]
History
Early Settlement and Colonial Era
New Castle County's roots extend to the early period of European contact with the Delaware Valley. The land that now forms the county was inhabited by Indigenous peoples long before European explorers arrived. Dutch, Swedish, and English colonial powers each sought control of the region over the seventeenth century, establishing a layered colonial legacy that left lasting marks on local place names, legal traditions, and architecture.
The town of New Castle itself became a focal point of early colonial governance. Its position along the Delaware River made it a natural hub for trade and administration, and for much of the colonial and early national period, it functioned as the seat of county government and a center of civic life. The city of New Castle was incorporated under an act of the state legislature in 1875, formalizing its municipal status.[2]
The Shift to Wilmington
For much of the nineteenth century, New Castle County's administrative and commercial center was in transition. In 1881, the county seat was formally moved from the city of New Castle to Wilmington, reflecting the latter city's growing importance as an industrial and transportation hub.[3] Wilmington's access to rail lines, its proximity to Philadelphia, and its expanding manufacturing base made it the dominant urban center in the state by the late nineteenth century.
The city of New Castle, meanwhile, retained its historic character and architectural fabric. Its historic district preserves a remarkable concentration of colonial and Federal-era buildings that reflect the town's long history as a center of governance and commerce. By 1860, only three percent of Black individuals in New Castle County were enslaved, and none of them lived in the town of New Castle itself—a statistic that distinguished the county from many other parts of the South and mid-Atlantic region during that era.[4]
Agricultural and Industrial Transitions
For most of its history, New Castle County was heavily agricultural, a pattern shared with Delaware as a whole. As late as the 1920s, Delaware ranked first in the country in certain measures of agricultural output, underscoring how deeply farming shaped the county's landscape and economy.[5] Over the course of the twentieth century, however, industrial development, suburbanization, and the growth of the corporate and financial sectors gradually transformed the county's economic base.
The expansion of Wilmington as a center for banking, chemical manufacturing, and corporate headquarters—particularly following Delaware's permissive corporate laws—drew significant investment and population growth into New Castle County throughout the twentieth century. This shift from an agricultural to a more diversified economy reshaped the county's demographics, infrastructure, and political character.
Geography and Communities
New Castle County occupies the northern tip of Delaware, a state notable for its compact geography. The county contains the state's most densely settled areas, including Wilmington and a ring of suburban communities that grew rapidly during the postwar decades. Rural and semi-rural areas persist in the southern portions of the county, where farmland and open space still characterize the landscape.
Major communities within the county include Wilmington, Newark, New Castle, Middletown, and Bear, each with distinct histories and characters. Wilmington functions as the county's urban core and Delaware's primary city. Newark is home to the University of Delaware, bringing a significant academic and research presence to the county. The historic city of New Castle, though no longer the county seat, retains its status as a place of considerable historical and architectural significance.
Development activity in the county continues into the contemporary period. An exploratory plan has been filed with New Castle County for a 1,362-acre property comprising three contiguous parcels to the east of existing developed areas, signaling ongoing interest in large-scale residential and commercial growth within the county's boundaries.[6]
Demographics and Diversity
New Castle County is the most demographically diverse of Delaware's three counties. According to data compiled from school enrollment figures in 2006, the county enrolled 71,763 students in its public schools. Of those, 34,384, or 48 percent, were White; 26,419, or 37 percent, were Black; 8,044, or 11 percent, were Hispanic; and 2,724, or 4 percent, were Asian. Native American students numbered 192, representing less than one percent of the total enrollment.[7]
The county ranks first of Delaware's three counties in classroom diversity. A diversity index measuring the probability that two students selected at random would belong to different ethnic groups stood at 62 percent in 2006, up from 46 percent in 1987.[8] This increase over roughly two decades reflects broader demographic changes driven in part by immigration, particularly growth in the county's Hispanic and Asian populations.
These enrollment figures, compiled as part of the Federal Common Core Data on school districts and obtained from the National Center for Education Statistics, are used as a tracking statistic and are not a direct count of immigrants. However, researchers note that changes in Hispanic and Asian student populations in the data are largely driven by immigration trends.[9]
Government and Politics
New Castle County is governed by an elected county executive and county council. The executive branch oversees county services, land use planning, law enforcement, and infrastructure. County council members represent geographic districts across the county and hold legislative authority over ordinances, budgets, and policy.
In the 2024 Democratic primary election for county executive, Marcus Henry won the Democratic nomination, a contest that saw close results across several of the accompanying races for county offices.[10] The county executive race is among the most closely watched local contests in Delaware, given the county's outsized share of the state's total population and voter base.
Delaware's corporate-friendly legal environment, centered in Wilmington within New Castle County, has long made the county a hub for the legal and financial industries. Thousands of corporations are incorporated under Delaware law, and the courts and law firms that support this corporate infrastructure are concentrated in Wilmington and its surrounding communities. This dynamic gives New Castle County an economic and political influence that extends well beyond its geographic boundaries.
Public Health
New Castle County, like counties across the United States, experienced the effects of the COVID-19 pandemic that began in 2020. Data tracking coronavirus cases, deaths, hospitalizations, and vaccinations within the county was compiled and published by national outlets during the course of the pandemic.[11] Updated tracking of virus hospitalizations, cases, deaths, tests, and vaccinations continued to be available for the county in subsequent years.[12]
The county's public health infrastructure, centered in part on Wilmington's hospital and medical facilities, served as the primary resource for county residents during the pandemic. The availability of detailed county-level data allowed public health officials and residents to monitor trends and respond to shifting conditions throughout the duration of the health emergency.
Historic Preservation
The city of New Castle, despite no longer serving as the county seat, retains an exceptional concentration of historic architecture and public spaces. The town's historic district encompasses streets, buildings, and open spaces that date to the colonial and early national periods. Preservation efforts in New Castle have maintained the visual and architectural character of the community, making it a resource for historians, architects, and visitors interested in early American urban form.[13]
The history of slavery and freedom in the county is also part of the historical record. By the eve of the Civil War, the vast majority of Black residents in New Castle County were free, with only three percent remaining enslaved as of 1860, and none of those enslaved individuals residing in the town of New Castle itself.[14] This history is documented and interpreted through local historical organizations and sites within the county.
See Also
- Wilmington, Delaware
- Newark, Delaware
- New Castle, Delaware
- Kent County, Delaware
- Sussex County, Delaware