[1] Originally known as Northern Berkshire Township Number 2 and including all of Hinsdale and part of Middlefield, the town was first settled in 1767 and was officially incorporated as Partridgefield in 1771.

John Leland, "because it is like the Peru of South America, a mountain town, and if no gold or silver mines are under her rocks, she favors hard money and begins with a P." On August 15, 1942, Garnet Peak (also known as Garnet Hill) in Peru was the site of a crash of a C-53 "Skytrooper" troop transport plane, resulting in the deaths of 16 of the 19 men on board.

Peru has the highest mean altitude in Massachusetts and, along with neighboring Windsor, is one of only two municipalities in the state with a mean elevation above 2,000 feet.

[6] It lies on high ground in the Berkshire Hills, with three main peaks in the town.

To the west of town, Ashmere Lake flows out into Bennett Brook, eventually reaching the East Branch of the Housatonic River.

The nearest national service is located at Bradley International Airport in Windsor Locks, Connecticut.

The population density is listed at 31.7 people per square mile (12.2/km2), ranking it 22nd in the county and 328th in the Commonwealth.

Peru employs the open town meeting form of government, and is led by a board of selectmen.

In the Massachusetts Senate, the town is part of the Berkshire, Hampshire and Franklin district, represented by Adam Hinds,[19] which includes all of Berkshire County and western Hampshire and Franklin counties.

[20] The town is patrolled by B4 (Cheshire) Barracks of Troop B of the Massachusetts State Police.