It was the first colony in Delaware, founded by the Dutch in 1631, and it remained the only significant European settlement in the region for some time.

Sussex County was not well defined until after 1760, following resolution of a dispute between William Penn's family and Frederick Calvert, 6th Baron Baltimore after intervention from the Crown.

Earlier Charles Calvert, 5th Baron Baltimore had argued that the county ended with Lewes, while Penn's sons stated it continued into Fenwick Island, which it now does.

The Mason–Dixon line was surveyed as part the agreement between the Penns and Lord Baltimore, and it has since defined the western and southern border of the county.

The county government hired ten commissioners to purchase land, build a courthouse and jail, and sell lots in an area at "James Pettyjohn's old field or about a mile from where Ebenezer Pettyjohn now lives," as the original order states, to encourage related development.

On May 9, 1791, the commissioners, under the leadership of the Delaware State Senator George Mitchell, purchased 76 acres (310,000 m2) for a townsite.

Eventually Georgetown was laid out in a circle one mile in diameter and centered around the original square surveyed by Shankland.

The new location proved better as an administrative center; Georgetown is still said to be "sixteen miles from everywhere" in Sussex County.

[5] Since the mid 20th century, the two most intense industries in Georgetown have been the Sussex County Courts and the raising and processing of chickens, largely grown on area farms under contract to a processor such as Purdue Farms which has a large chicken processing plant in Georgetown.

It has attracted numerous immigrants from Haiti and Guatemala as workers, stimulating growth of the population and changing the town's demographics.

In 2000 slightly more than one-third of the population was ethnic Hispanic and one-fifth was African American (including Haitians).

Together with the losers and the chairs of the county's political parties, they ceremonially "bury the hatchet" in a tub of sand.

[8] Georgetown is unusual among Delaware municipalities as the town was constructed around a circle, instead of the more traditional park square.

[10] According to the United States Census Bureau, the town has a total area of 4.1 square miles (11 km2), all land.

The main north–south road in Georgetown is US 113, which passes through the western part of town on Dupont Boulevard and heads south to Millsboro and Pocomoke City, Maryland and north to Milford, where it connects to DE 1 that heads north to Dover and Wilmington.

US 9 runs southwest–northeast through Georgetown on Market Street, heading southwest to Laurel and northeast to Lewes and the Cape May–Lewes Ferry across the Delaware Bay.

DE 404 passes through Georgetown as part of a route linking the Baltimore-Washington Metropolitan Area and the Chesapeake Bay Bridge to the Delaware Beaches, entering town from the west concurrent with DE 18 to The Circle, where it joins US 9 and heads northeast along with that route toward the beaches.

[16] The Delaware Coastal Airport is located to the east of Georgetown, offering general aviation.