Sunderland is a town in Franklin County, Massachusetts, part of the Pioneer Valley. The population was 3,777 at the 2000 census. It is part of the Springfield, Massachusetts Metropolitan Statistical Area. Sunderland was first settled in 1713 and was officially incorporated in 1714. It was first known as Swampfield, a name which is now honored by Swampfield Road, but the name was changed to attract more residents. It was renamed in honor of Charles Spencer, the Earl of Sunderland. Historically, the land was largely used for farming. Before the incorporation of Leverett in 1774, that town was a part of Sunderland's territory.