Where is Rockingham County?

3 Rockingham Counties in 3 states · 507,588 people (2025)

There are 3 counties named Rockingham County in the United States, in New Hampshire, North Carolina and Virginia. The most populous is Rockingham County, New Hampshire (county seat: Brentwood), with 324,077 people in 2025. 3 of them are named after Charles Watson-Wentworth, 2nd Marquess of Rockingham, British Prime Minister (1730-1782).

Map of the United States showing where all 3 Rockingham Counties are, labeled by state
Every Rockingham County in the United States (red), labeled with its state. Boundaries: U.S. Census Bureau, 2025. Free to use with attribution (CC BY 4.0).

All 3 Rockingham Counties

Sorted by state. Each link opens the county's map.

StateCounty seatPopulation 2025Land area (sq mi)EstablishedNamed after
Rockingham County, New HampshireBrentwood324,0776961769Charles Watson-Wentworth, 2nd Marquess of Rockingham
Rockingham County, North CarolinaWentworth94,1955661785Charles Watson-Wentworth, 2nd Marquess of Rockingham
Rockingham County, VirginiaHarrisonburg89,3168501778Charles Watson-Wentworth, 2nd Marquess of Rockingham

Questions about Rockingham Counties

How many Rockingham Counties are there?

There are 3 Rockingham Counties in the United States, in New Hampshire, North Carolina and Virginia.

Which Rockingham County is the largest?

By population, Rockingham County, New Hampshire (324,077 people in 2025). By land area, Rockingham County, Virginia (850 sq mi).

Which Rockingham County is the oldest?

Rockingham County, New Hampshire, established in 1769. The newest is Rockingham County, North Carolina (1785).

Why are there so many Rockingham Counties?

3 of the 3 are named after Charles Watson-Wentworth, 2nd Marquess of Rockingham, British Prime Minister (1730-1782). Many counties took their names from the same founders, presidents and generals as new states were organized.

How do I find out which Rockingham County an address is in?

Open the county map of the state: it has a search box for cities, towns and ZIP codes. On a phone, the "what county am I in" tool on our sister site uses your location.

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Other common county names