Historical and archaeological evidence suggests that the earliest settlements in the regions that today comprise Maine go back to 3000 BCE.
European contact with Maine is believed to have begun in the 11th century, with the arrival of Vikings under Leif Erikson. The Portuguese explorer Estevao Gomes explored the coastline of the region in 1525.
The French and the English set up competing settlements in the region throughout the 17th century, such as those in Phippsburg and Castine.
The first reference to the Province of Maine occurs in 1622, with respect to a land patent that was awarded to Sir Ferdinando Gorges and John Mason for the area that lay between the rivers Merrimack and Kennebec. Settlements along present-day Somerset County and Portland contributed to the founding of Maine.
The region's boundaries, name, and ownership changed several times over the next 150 years.
Under the terms of the Missouri Compromise, Maine emerged as America's 23rd state on March 15, 1820.