Georgetown is a town in and the county seat of Sussex County, Delaware, United States. According to the 2010 census, the population of the town is 6,422, an increase of 38.3% over the previous decade.Georgetown is part of the Salisbury, Maryland-Delaware Metropolitan Statistical Area.HistorySecond county seatLewes, sited on the Delaware Bay, was designated as the first county seat. 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. When English colonists William Penn organized the three southern counties of Pennsylvania, which are now Delaware, Lewes was the natural choice for the location of the Sussex County's Seat of Justice.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. This dispute over borders had delayed discussion over the location of a county seat. 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. Georgetown, located more centrally in the county, was later designated as its seat for court.