The Pequot War, war fought in 1636–37 by the Pequot people against a coalition of English settlers from the Massachusetts Bay, Connecticut, and Saybrook colonies and their Native American allies (including the Narragansett and Mohegan) that eliminated the Pequot as an impediment to English colonization of southern New England. It was an especially brutal war and the first sustained conflict between Native Americans and Europeans in northeastern North America.
The war lasted 11 months and involved thousands of combatants who fought several battles over an area encompassing thousands of square miles. In the first six months of the war, the Pequot, with no firearms, won every engagement against the English. Both sides showed a high degree of sophistication, planning, and ingenuity in adjusting to conditions and enemy countermeasures. While the Pequot War was the first time that the English had confronted Native American battle formations, tactics, and weapons in New England, the Pequot had already encountered European battle formations and methods during a brief war they fought with the Dutch in 1634, as a result of which they had adjusted their tactics to battle the English. Indeed, the English suffered dozens of casualties in the early stages of the war before they were able to adapt their Old World military experiences to the battlefields of the New World and win decisive engagements.
In the end, the Pequot War forever changed the political and social landscape of southern New England, and it influenced colonial and U.S. policies toward Native Americans for centuries. The massacre of the Pequot at Mistick demonstrated to all observers, in southern New England and elsewhere, the English ability and will to wage total war against their Indian enemies. Continue reading from Britannica