The Town of Peru is in the eastern part of the county and is south of Plattsburgh.
The town was first settled in 1772. The Battle of Valcour Island was fought in Lake Champlain in the eastern part of Peru in 1776.
Peru was formed from parts of the Town of Plattsburgh and the Town of Willsboro (the latter now in Essex County, New York) in 1792. Part of Peru was returned to Willsboro in 1799. In 1838, part of the town was used to form the Towns of Au Sable and Black Brook.
On April 20, 2002, around 6:50 am, a magnitude 5.2 earthquake was centered in Keeseville, approx. 15 miles south of Peru. The earthquake was felt as far north as Montreal, as far west as Michigan and Ohio, as far south as Washington, D.C., and as far east as Boston, MA and Maine. No injuries or deaths were reported, however moderate damage in the epicentral area was common to include partial road collapses, fallen chimneys, and broken windows.
In the year 2001 the Peru football team went undefeated and won the New York state Class B championship game.