The river's name in derived from an Algonquin Indian word and means long tidal river. The first European to see the river was the Dutch explorer Adriaen Block in 1614. The first English colonist to record his visit was Edward Winslow from the Plymouth Colony in 1632. In 1633 the English built at trading post on the site of Windsor, Connecticut and the Dutch built one with a fort at the site of Hartford, Connecticut. As the number of English colonists increased, the Dutch abandoned their enterprise in 1654.
At first the broad, fertile valley attracted agricultural colonies, but the volume and fall of the river contributed to the rise of manufacturing in the valley. The greatest single drop of 58 feet (17.5 meters) is at Holyoke, Massachusetts. Other important centers include Windsor and Hartford in Connecticut, Springfield, Massachusetts, and Brattleboro, Vermont.
The Connecticut River Flood Control Compact was established n 1953 in response to severe flooding. The Clean Water Act in 1965 has also had a major impact on the Connecticut River and its tributaries.