Aroostook War Summary

  • Last updated on November 10, 2022

A long-standing failure to define the border between Maine and Canada led to tension and military mobilization in 1838 and 1839, but restraint on both sides resulted in the conflict being resolved without bloodshed.

Summary of Event

By the standards of the twenty-first century, the Treaty of Paris that ended the American Revolution (1775-1783) American Revolution (1775-1783);settlement of and guaranteed the independence of the United States was astonishingly brief, only two thousand words in length. This brevity led to complications later. The entire definition of the boundary of Maine with Canada provided in the treaty is as follows: Aroostook War (1838-1839) Maine;borders Canada;borders Borders, U.S.;with Canada[Canada] New Brunswick;and Aroostook War[Aroostook War] Native American wars;Aroostook War [kw]Aroostook War (1838-1839) [kw]War, Aroostook (1838-1839) Aroostook War (1838-1839) Maine;borders Canada;borders Borders, U.S.;with Canada[Canada] New Brunswick;and Aroostook War[Aroostook War] Native American wars;Aroostook War [g]United States;1838-1839: Aroostook War[2030] [g]Canada;1838-1839: Aroostook War[2030] [c]Diplomacy and international relations;1838-1839: Aroostook War[2030] [c]Expansion and land acquisition;1838-1839: Aroostook War[2030] [c]Wars, uprisings, and civil unrest;1838-1839: Aroostook War[2030] Scott, Winfield Scott, Winfield [p]Scott, Winfield;and Aroostook War[Aroostook War] Harvey, Sir John Webster, Daniel Ashburton, First Baron William I (king of Netherlands)

And that all disputes which might arise in future on the subject of the boundaries of the said United States may be prevented, it is hereby agreed and declared, that the following are and shall be their boundaries, viz.; from the northwest angle of Nova Scotia Nova Scotia , viz., that angle which is formed by a line drawn due north from the source of St. Croix River to the highlands; along the said highlands which divide those rivers that empty themselves into the river St. Lawrence, from those which fall into the Atlantic Ocean, to the northwesternmost head of Connecticut River. . . .

A controversy developed over the exact meaning of rivers that “fall into the Atlantic Ocean.” The United States definition was that any river not flowing to the St. Lawrence proper flowed instead to the Atlantic. This interpretation created a boundary well north of the present boundary. The British definition, in effect, held that only rivers flowing to the open ocean flowed “into the Atlantic” and that rivers flowing to the Gulf of St. Lawrence or the Bay of Fundy were flowing into British territorial waters. This interpretation created a southern boundary that placed the northern quarter of the present state of Maine in Canada.

At the center of the controversy was the watershed of the St. John River, which flows from Quebec around northern Maine, then across New Brunswick to the Bay of Fundy. Although timber resources eventually came to dominate the controversy, the most significant concern to the British was maintaining secure land communication between Quebec and the present Maritime Provinces;transportation Maritime Provinces. An additional concern was sovereignty over British settlers who had moved into the disputed area.

In 1817, the Boundary Commission met in Boston and appointed surveyors to map the boundary. The commission met again in 1821 to hear the surveyors’ final report. When the commission failed to agree on a boundary, they fell back on a provision in the Treaty of Ghent to submit the controversy to a “friendly sovereign or state.” The need for such arbitration was growing increasingly clear. After Maine achieved statehood in 1820, American settlement in the disputed area began to grow. In 1825, a Maine official was arrested on charges of interfering with British affairs in the area, but he was released after diplomatic pressure from Washington. Over the next few years, there were occasional arrests of both American and British officials for carrying out their official duties in areas claimed by the other side.

In 1827, William I, king of the Netherlands, agreed to arbitrate the boundary dispute. In his decision, delivered in 1831, he stated that the conflicting interpretations and the ambiguity of the treaty terms made it impossible to render a definitive judgment. Instead he proposed a compromise boundary along the St. John River. The U.S. envoy to the Netherlands immediately criticized the suggestion as going beyond the bounds of the original arbitration request, and the U.S. Senate rejected the proposed compromise after Maine filed a formal protest over its loss of territory. Ironically, this settlement would have given the U.S. 893 square miles more territory than it eventually received under the final treaty.

The crisis reached a new peak in 1838, when a Maine land commissioner, sent to arrest British lumbermen cutting timber on lands claimed by Maine, was arrested himself. The Maine legislature responded by voting funds for defense, and Governor Edward Kent sent troops north. This appears to be the only time in U.S. history that a state has acted unilaterally against another country. New Brunswick also sent militia into the region. Interestingly, war fever seems to have been at least as high in Nova Scotia Nova Scotia , which approved funds and the sending of militia in case New Brunswick was attacked.

President Martin Van Buren sent General Winfield Scott Scott, Winfield Scott, Winfield [p]Scott, Winfield;and Aroostook War[Aroostook War] to northern Maine with instructions to prevent hostilities and work out an arrangement with British authorities for maintaining the peace. Scott and Sir John Harvey Harvey, Sir John , lieutenant governor of New Brunswick, arranged an informal demarcation in an agreement signed on March 25, 1839. Although there was a fair amount of saber rattling and militarism among the Maine volunteers and state politicians, the actual level of violence in the conflict was almost nonexistent. There were no fatalities due to direct military action, although a few soldiers stationed in northern Maine died, probably from illness, accident, or exposure.

When Daniel Webster Webster, Daniel Webster, Daniel [p]Webster, Daniel;and Webster-Ashburton Treaty[Webster Ashburton Treaty] became secretary of state in 1841, he had already become convinced that the old approach of attempting to read the fine print in the 1783 and 1815 treaties was a failure and that only a completely new approach could resolve the issue. He suggested to the British that the boundary be redefined by convention, and the British dispatched Alexander Baring, the first Baron Ashburton, with full authority to negotiate. After numerous conferences in 1841 and 1842, they defined the boundary as it now stands. Webster persuaded representatives of Maine and Massachusetts to accept the compromise by claiming that the territory allocated to Maine was far more valuable than the portion granted to Canada. They were further placated by funds from the federal government reimbursing both states for expenses they had incurred in dealing with the controversy.

Because both Webster and Ashburton had conceded territory to the other, both were harshly criticized in some quarters. Nevertheless, the treaty was signed on August 9, 1842, and ratified by both countries. Surveyors were appointed in 1843 to map the agreed boundary, and they submitted their final report in 1847. The most enduring relic of the Aroostook War is Fort Knox on the Penobscot River south of Bangor, Maine (not to be confused with the famous gold repository in Kentucky). The fort was built to protect the Maine lumber trade from possible future threats and was completed in 1844. Although a substantial piece of military architecture, it never saw action. It was lightly garrisoned during the U.S. Civil War (1861-1865) and Spanish-American War (1898) and is now a Maine state park.


The Aroostook War has an almost comical aspect in that it involved passionate feelings and strident talk of war over a remote area where neither side was really threatened. Nevertheless, it was the sort of minor local conflict that all-too-often spirals out of control into a major conflict. Although there was a fair amount of rash talk and action by the public and by some Maine politicians, and there were even face-offs between the Maine and New Brunswick militias, the conflict did not escalate. Almost all of the senior military and political officials involved wanted to avoid war, recognized that the issues were simply not great enough to justify conflict, and sought to ease tensions whenever possible.

Winfield Scott served with distinction in the Mexican War (1846-1848). In 1859 he was sent to the Pacific Northwest to help defuse a boundary confrontation between Britain and the United States over islands between present-day Washington and British Columbia British Columbia . That conflict, like the Aroostook War, was kept contained because of the reluctance of leaders on both sides to allow a minor issue to escalate. Scott thus helped maintain peace during crises at opposite ends of the U.S.-Canadian border.

Further Reading
  • citation-type="booksimple"

    xlink:type="simple">Dunbabin, John P. “The 1831 Dutch Arbitration of the Canadian-American Boundary Dispute: Another View.” New England Quarterly 75, no. 4 (2002): 622-646. Makes extensive use of Dutch documents to analyze the role of the Netherlands in attempting to resolve the Maine-New Brunswick border dispute.
  • citation-type="booksimple"

    xlink:type="simple">Sassaman, Richard. “A Borderline War.” American History 35, no. 6 (2001): 20-27. Survey of the Maine-New Brunswick boundary dispute from its origins to its successful resolution.
  • citation-type="booksimple"

    xlink:type="simple">Shortt, Adam, and Arthur G. Doughty, eds. Canada and Its Provinces: A History of the Canadian People and Their Institutions. Vol. 8. Toronto: T. A. Constable, 1913. Contains detailed accounts of the boundary negotiations and excerpts from important documents.
  • citation-type="booksimple"

    xlink:type="simple">Van Zandt, Franklin K. Boundaries of the United States and the Several States. Washington, D.C.: U.S. Department of the Interior, 1976. Describes the evolution of United States international and internal boundaries, including the Aroostook boundary dispute and its resolution.
  • citation-type="booksimple"

    xlink:type="simple">Wagner, Michael D. “’A Few Days Later in Coming’: Major General Winfield Scott’s Role in the Aroostook War.” Maine History 34, nos. 3-4 (1995): 162-177. Explains how General Winfield Scott negotiated a military stand-down with the lieutenant governor of New Brunswick.

War of 1812

Treaty of Ghent Takes Effect

Missouri Compromise

Congress Passes Land Act of 1820

Rebellions Rock British Canada

U.S. Election of 1840

Upper and Lower Canada Unite

Webster-Ashburton Treaty Settles Maine’s Canadian Border

Related Articles in <i>Great Lives from History: The Nineteenth Century, 1801-1900</i>

Winfield Scott; Martin Van Buren; Daniel Webster. Aroostook War (1838-1839) Maine;borders Canada;borders Borders, U.S.;with Canada[Canada] New Brunswick;and Aroostook War[Aroostook War] Native American wars;Aroostook War

Categories: History