Western Massachusetts is an area located within the Commonwealth of Massachusetts, which is part of the United States region of New England. Despite its relatively small size, geographically, it features diverse topography, and outsized contributions to American history and culture, owing in large part to its 22 universities, approximately 100,000 university students, and institutions, (such as Tanglewood, Springfield Armory, Jacob's Pillow, etc.)

For the former town in Bristol County, Massachusetts, see Warren, Rhode Island.

Warren is a town in Worcester County, Massachusetts, United States. The population was 5,135 at the 2010 census.