Caribou is a city in Aroostook County, Maine, USA. According to the 2010 US Census, the city's population is 8189. Watch camera online in Caribou History The first settlements that appeared in the early 19th century on the territory of modern Caribou were hunter-trapper and lumberjack camps. Between 1838 and 1840, a border conflict erupted between the United States and the British Empire, known as the Aroostook War, during which, in 1838, a bloodless skirmish took place in the Caribou region between lumberjacks from Maine and the Canadian province of New Brunswick. In 1842, the Webster-Ashburton Treaty was concluded between the conflicting parties, according to which the territory on which the city later arose was ceded to the United States.