Major cities in the Merrimack Valley include Concord, Manchester, and Nashua in New Hampshire, and Lowell, Lawrence, and Haverhill in Massachusetts.

[4] The earliest European records of the river date to a French expedition under Pierre du Guast, Sieur de Monts, in 1605.

[5] The city of Newburyport, first settled in 1635, at the river's mouth, became an important shipbuilding center during the colonial era, using lumber floated downriver from the White Mountains.

Its prominence was diminished when the Middlesex Canal was completed in the first quarter of the 19th century, allowing lumber to be shipped directly downriver from the White Mountains to Charlestown, Massachusetts, and improving connections between Boston and the Merrimack Valley.

Textile production spread up and down the Merrimack Valley in both states for the next century, but eventually was eclipsed after the Second World War.

Lawrence was the site of the Bread and Roses strike, a landmark event in the history of labor relations in the United States.

After a few decades of stagnation, the "Massachusetts Miracle" came to the valley, bringing the headquarters of Wang Laboratories to Tewksbury, then Lowell.

[citation needed] Lawrence is the birthplace of actress Thelma Todd, composer/conductor Leonard Bernstein and actor/singer Robert Goulet.

West Newbury is the birthplace of John Cena, a WWE professional wrestler, actor, former rapper, and television personality.

[14][15] Institutes of higher learning include Hockey East rivals UMass Lowell and Merrimack College.

Software company UKG is one of the largest private employers in the region, as is Philips, whose medical division is based in Andover.

Many major highways (including I-93, I-95, and US 3) and several heavily used lines of the MBTA Commuter Rail system provide easy access to the city from the Merrimack Valley.

Institutions of higher education include: While the textile industry that served as the underpinning of the Merrimack Valley has disappeared, the region has since transferred to other economic activities.

Sanders Associates, a major defense contractor based in Nashua has, through several mergers and acquisitions, become a division of BAE Systems Inc. and is one of the regions largest employers.