Plymouth is a town in Grafton County, New Hampshire, United States, in the White Mountains Region. Plymouth is located at the convergence of the Pemigewasset and Baker rivers, both of which are components of the Merrimack River watershed.

The population was 5,892 at the 2000 census, and the town is home to Plymouth State University, Speare Memorial Hospital, and Plymouth Regional High School. Plymouth was originally the site of an Abenaki village that was burned to the ground by Captain Thomas Baker in 1712. This was just one of the many British raids on American Indian settlements during Queen Anne's War. Part of a large plot of undivided land in the Pemigewasset Valley, the town was first named New Plymouth, after the original Plymouth Colony in Massachusetts. Colonial Governor Benning Wentworth granted Plymouth to settlers from Hollis, all of whom had been soldiers in the French and Indian War. Some had originally come from Plymouth, Massachusetts. The town was incorporated in 1763.[1] Parts of Hebron and Campton were annexed in 1845 and 1860.