Brunswick was created in 1720 from Prince George County. Jurisdiction (court, militia and land records) remained with Prince George County until 1732. The county is named for the former Duchy of Brunswick-Lunenburg in Germany, because one of the titles also carried by Britain's Hanoverian kings was Duke of Brunswick-Lunenburg. In 1732 the county received more land from parts of Surry and Isle of Wight counties. Brunswick County reached to the Blue Ridge Mountains until 1745, when increasing population in the region resulted in the formation of a series of new counties, and Brunswick's current western border was established.
Nottoway County on the north, Dinwiddie County to the northeast, Greensville County on the east, Warren County, NC in the south, Mecklenburg County on the west and Lunenburg County to the northwest.