As Maine's northernmost county, its northernmost town, Estcourt Station, is therefore also the northernmost town of New England and of the continental U.S. east of the Great Lakes.
Aroostook County is known for its potato crops, as well as its French culture. In the northernmost region of the county, which borders Madawaska County, New Brunswick, a majority of residents are bilingual. In some communities, it is difficult to find employment for those who do not speak both English and French. Employers such as pharmacies, hospitals, banks, and post offices encounter this most frequently. The county is a hub for wind power, with so much being produced that the county will soon have excess to sell once it connects to the New England Power Grid.
As of the census of 2000, there were 73,938 people, 30,356 households, and 20,429 families residing in the county. The population density was 11 people per square mile (4/km²). There were 38,719 housing units at an average density of 6 per square mile (2/km²). The racial makeup of the county was 96.80% White, 0.38% Black or African American, 1.36% Native American, 0.47% Asian, 0.03% Pacific Islander, 0.17% from other races, and 0.80% from two or more races. 0.60% of the population were Hispanic or Latino of any race. 22.6% were of French, 15.4% United States or American, 14.6% English, 14.3% French Canadian and 10.2% Irish ancestry. According to the 2000 United States Census, 22.37% of the population speak French at home.
There were 30,356 households out of which 28.40% had children under the age of 18 living with them, 55.60% were married couples living together, 8.10% had a female householder with no husband present, and 32.70% were non-families. 27.60% of all households were made up of individuals and 13.10% had someone living alone who was 65 years of age or older. The average household size was 2.36 and the average family size was 2.86.
In the county the population was spread out with 22.60% under the age of 18, 7.90% from 18 to 24, 26.30% from 25 to 44, 26.20% from 45 to 64, and 17.00% who were 65 years of age or older. The median age was 41 years. For every 100 females there were 95.40 males. For every 100 females age 18 and over, there were 92.70 males.
The median income for a household in the county was $28,837, and the median income for a family was $36,044. Males had a median income of $29,747 versus $20,300 for females. The per capita income for the county was $15,033. About 9.80% of families and 14.30% of the population were below the poverty line, including 16.20% of those under age 18 and 16.00% of those age 65 or over.