A map of the boundary line explored in 1817
Maine Historical Society
Text by Richard Judd
Images from Maine Historical Society
Maine's timber resources had drawn the British, who needed the forest resource for masts and shipbuilding, to the area by the 16th century. That need continued, but when the American colonies declared their independence in 1776, Britain had to go farther north for its timber.
Americans, also, had plenty of uses for the resource. Strong markets in the expanding seaboard cities pushed the frontier of lumbering activity from the Piscataqua to the Kennebec Valley by 1800, and north to the Penobscot headwaters in the 1840s.
St. John and Penobscot Rivers map, 1798
Maine Historical Society
As the industry moved north of the Penobscot waters, it became a source of tension between Maine and its eastern neighbor, New Brunswick. The negotiators who drafted the Treaty of Paris that ended the Revolutionary War had failed to specify a clear boundary between Maine and New Brunswick, but while the “disputed territory” remained unsettled, little thought was given to defining it.
In 1796, negotiators ran a "monument line" due north from the St. Croix River’s headwaters to what was described in the treaty as the "highlands" separating rivers draining into the St. Lawrence from those entering the Atlantic – the agreed-upon northern boundary.
Maine insisted this height of land was north of the St. John, while New Brunswick saw the Penobscot watershed as the boundary. Settlement in the 1820s brought tensions, and these were exacerbated when lumber operators from Maine and New Brunswick converged on the timber adjacent to the Aroostook, Allagash, and St. John rivers.
Treaty of Washington boundary map, 1842
Maine Historical Society
Maine declined to accept what was known as the King of the Netherlands' line – a settlement that would have given the U.S. a portion of the disputed territory that is similar to the current boundaries – the St. John and St. Francis rivers. In the meantime, Madawaska – in the disputed territory – incorporated as part of Maine.
Maine continued to push the limits of what President Andrew Jackson wanted it to do in the territory in part because many in Maine did not want the federal government to make the decision and in part because of political disputes and maneuverings within the state.
Tensions continued in the area. The British in 1833 charged Maine and Massachusetts with encouraging settlement, building roads, and offering inducements to cut timber in the disputed territory. Maine denied the charges. Officials in Canada feared an invasion by Maine.
In 1839 disputes over timber theft on the disputed lands culminated in the so-called bloodless Aroostook War. Maine sent troops to the hastily constructed Forts Fairfield and Kent, and New Brunswick deployed theirs across the St. John.
Cartoon of Northeast Boundary dispute, ca. 1842
Maine Historical Society
As tensions mounted, the federal government got involved. President Martin Van Buren sent General Winfield Scott to Augusta with authority to negotiate a peace or lead the nation to war. Astute bargaining between Scott and New Brunswick Lieutentant-Governor John Harvey averted hostilities, and the boundary was settled in 1842 after negotiations between Daniel Webster and Lord Ashburton (Alexander Baring) culminated in the Webster-Ashburton Treaty.
The U.S. got about two-thirds of the disputed land, navigation rights on the St. John and generally favorable terms across the northern border to Minnesota.