- POCUMTUC HISTORY Pocumtuc Location The Connecticut River Valley of western Massachusetts from just south of the border with Connecticut northward into southern Vermont and southwestern New Hampshire. Population Perhaps as many as 5, 000 in 1600, the Pocumtuc population declined rapidly from epidemic and wars with the Iroquois and English. For the most part, the Pocumtuc were destroyed during ...www.dickshovel.com/pocu.html