 One early 19th century author explained that this name originally referred to a specific tree along the river in the area of modern-day Beacon Falls, but came to be applied broadly to the entire river over time.The valley was later settled in the 17th century by English colonists.Given its rocky soil, which was not good for farming, and the high potential for water power, the Naugatuck Valley became an industrialized area in the 19th century.