Granted on November 7, 1780, Cambridge was chartered on August 13, 1781 to Samuel Robinson, John Fassett, Jr., Jonathan Frost and 64 others. It was first settled in 1783 by John Safford from Piermont, New Hampshire. The intervales proved good but rough, best for grazing livestock. By 1839, the town had about 7,000 sheep. The Lamoille River offered water power for watermills. Industries included one woolen factory, one tannery, one gristmill, plus several sawmills and cabinet shops. Cambridge and neighboring Johnson were together known as the King's College Tract, being created by Lieutenant Governor Cadwallader Colden by authority of BritishKing George III in 1764. The King's College Tract was reserved for the eventual establishment of a university on the site. The place name Cambridge suggests Cambridge University in England. Johnson, the other town in the King's College Grant, was named for William Samuel Johnson. Both the St. Johnsbury & Lake Champlain Railroad and the Burlington & Lamoille Railroad passed through the town. The former is now the Lamoille Valley Rail Trail.
As of the census of 2000, there were 3,186 people, 1,266 households, and 886 families residing in the town. The population density was 50.0 people per square mile. There were 1,363 housing units at an average density of 21.4 per square mile. The racial makeup of the town was 96.52% White, 0.25% Black or African American, 0.56% Native American, 0.13% Asian, 0.06% from other races, and 2.48% from two or more races. Hispanic or Latino of any race were 0.75% of the population. There were 1,266 households, out of which 32.8% had children under the age of 18 living with them, 60.3% were married couplesliving together, 6.9% had a female householder with no husband present, and 30.0% were non-families. 20.1% of all households were made up of individuals, and 5.5% had someone living alone who was 65 years of age or older. The average household size was 2.51 and the average family size was 2.91. In the town, the population was spread out, with 24.4% under the age of 18, 7.6% from 18 to 24, 35.9% from 25 to 44, 23.6% from 45 to 64, and 8.6% who were 65 years of age or older. The median age was 36 years. For every 100 females, there were 101.3 males. For every 100 females age 18 and over, there were 102.3 males. The median income for a household in the town was $44,950, and the median income for a family was $49,274. Males had a median income of $35,264 versus $23,199 for females. The per capita income for the town was $20,527. About 2.9% of families and 5.2% of the population were below the poverty line, including 2.3% of those under age 18 and 5.9% of those age 65 or over.
