Portsmouth, city, Rockingham County, southeastern New Hampshire, a seaport on the Atlantic Ocean and on the Piscataqua River, opposite Kittery, Maine; settled 1623, incorporated as a city 1849. It is a commercial, manufacturing, fishing, and tourist center. Products include processed seafood, footwear, electronic equipment, cable, gypsum goods, and industrial machinery. The great Portsmouth Naval Shipyard (situated in Kittery) is important to the local economy. Points of interest include Strawbery Banke, a restoration of the settlement as it was in colonial times; the Richard Jackson House (circa 1664); and the John Paul Jones House (1758), where the naval hero lived in 1777 while his ship, the Ranger, was being built. A junior college is in the city. The community, named for Portsmouth, England, was the capital of colonial New Hampshire. The Treaty of Portsmouth, ending the Russo-Japanese War, was signed at the Portsmouth Naval Shipyard in 1905. Population 26,254 (1980); 25,925 (1990); 20,784 (2000).
