Rochester was founded in 1679 on the lands called "Sippican" by the local Wampanoags, along the coast of Buzzards Bay (Sippican was the name of the local tribe). It originally included the lands of Mattapoisett, Marion and parts of Wareham (which was lost when Wareham was founded in 1739). The town was officially incorporated on June 4, 1686 as Rochester, and was renamed for Rochester, England, from which early settlers to the town came. The town originally thrived with the early shipbuilding and whaling trade in Mattapoisett Harbor. However, in 1852 and 1857 the towns of Marion and Mattapoisett, respectively, were separated and incorporated as separate towns, thus land-locking Rochester. Since that time, the town has become mostly rural-residential, with some farms located in town. Rochester is a "Right to Farm" community.
The town of Rochester has a total area of 36.4 square miles (94 km), of which 33.9 square miles (88 km) is land and 2.5 square miles (6.5 km), or 6.76%, is water. Rochester is located along the western border of Plymouth County, and is bordered by Lakeville and Middleborough to the north, Wareham and Marion to the east, Mattapoisett to the south, and Acushnet and Freetown to the west. The town's localities include Bisbee Corner, East Rochester, North Rochester and Varella Corner. The town is about 10 miles (16 km) northeast of New Bedford, 40 miles (64 km) east of Providence, Rhode Island, and 60 miles (97 km) south of Boston. Rochester’s population is 5,698 with 3,860 registered voters.
Rochester is represented by state Senator Michael Rodrigues (D-Westport) as a part of the First Bristol and Plymouth District of the Massachusetts Senate and by state Representative William M. Straus (D-Mattapoisett) as a part of the Tenth Bristol District of the Massachusetts House of Representatives. The town is patrolled by the Seventh (Bourne) Barracks of Troop D of the Massachusetts State Police.
On the national level, Rochester is a part of Massachusetts's 9th congressional district, and is currently represented by William R. Keating. The state's senior member of the United States Senate is Elizabeth Warren. The junior senator is Ed Markey.
The town uses the open town meeting form of government, led by a board of selectmen. The town hall is located at the Town Common along Route 105. The town's police department, post office and the Joseph H. Plumb Memorial Library (a part of the SAILS library network) are located nearby. The volunteer fire department is located closer to the geographic center of town. The town's Highway Department is located near Varella Corner, and is responsible for snow removal and road upkeep. In 2012, the town adopted a "Right-to-Farm" bylaw which "encourages the pursuit of agriculture, promotes agriculture-based economic opportunities, and protects farmlands within the Town of Rochester by allowing agricultural uses and related activities".