Named for the many eagles found at the lake during the time of the Aroostook War, Eagle Lake was settled in the 1840s by French-Acadian and Irish immigrants. It was first organized for election purposes on July 11, 1859 from the unorganized township T16 R6. After several organizations and reorganizations, it was incorporated as a town on March 16, 1911.
Eagle Lake spawns the Fish River, which empties into the St. John River at Fort Kent, Maine. Maine Route 11 serves as the main route through Eagle Lake, beginning at Fort Kent and moving through Eagle Lake south through the western part of Aroostook County.