The Webster–Ashburton Treaty, signed August 9, 1842, was a treaty
that resolved several border issues between the United States and the
British North American colonies (the region that became Canada).
Signed under John Tyler's presidency, it resolved the Aroostook War, a
nonviolent dispute over the location of the Maine–New Brunswick
Established the border between Lake Superior and the Lake of the
Woods, originally defined in the Treaty of Paris in 1783
Reaffirmed the location of the border (at the 49th parallel) in the
westward frontier up to the
Rocky Mountains defined in the Treaty of
Defined seven crimes subject to extradition
Called for a final end to the slave trade on the high seas
Agreed that the two parties would share use of the Great Lakes
The treaty retroactively confirmed the southern boundary of Quebec
that land surveyors John Collins and Thomas Valentine had marked with
stone monuments in 1771–3. The treaty intended that the border be at
45 degrees north latitude, but is in some places nearly a half mile
north of the parallel. The treaty was signed by United States
Secretary of State
Daniel Webster and British diplomat Alexander
Baring, 1st Baron Ashburton.
1 In the East
2 In the West
3 Other issues
5 See also
8 Works cited and further reading
9 External links
In the East
Settlement in the East
An arbitration of various border issues in the East before King
William I of the Netherlands
William I of the Netherlands in 1831 had failed to yield a binding
The Treaty of Paris had established the 45th parallel as part of the
northern boundary of modern-day New York and Vermont. Most of that
portion of the boundary had previously been surveyed in the early
1770s, but the survey line was inaccurate. Since "Fort Blunder"—an
unnamed U.S. fort in what is now part of northeastern New York—had
been constructed north of the actual 45th parallel, the United States
wanted to follow the old survey line, and the Webster–Ashburton
treaty incorporated this change, leaving the half-finished fort on
U.S. soil. Following signing of the treaty, the U.S. resumed
construction on the site. The new project replaced the aborted
1812-era construction with a massive third-system masonry
fortification known as Fort Montgomery.
This treaty marked the end of local confrontations between lumberjacks
(known as the Aroostook War) along the Maine border with the British
colonies of Lower Canada and New Brunswick. The newly agreed border
divided the disputed territory between the two nations. The British
acquired the Halifax–Quebec road route, which their military desired
because it provided a wintertime connection between Lower Canada and
New Brunswick and Nova Scotia. The treaty adjusted portions of the
border to give the United States a little more land to the north. It
also resolved issues that had led to the Indian Stream dispute as well
as the Caroline Affair. The Indian Stream area was assigned to the
United States. The
Webster–Ashburton Treaty failed to clarify
Machias Seal Island
Machias Seal Island and nearby North Rock, which remain
in dispute today. Additionally, the signing of the treaty put an
end to several building improvements planned for Upper Canadian
defense forts such as
Fort Malden in Amherstburg, which the British
government later abandoned, as they no longer served a defensive
In the West
Plaque in Washington, D.C.
The border between Lake Superior and the
Lake of the Woods
Lake of the Woods needed
clarification because the faulty
Mitchell Map used in the negotiations
for the Treaty of Paris was inadequate to define the border according
to the terms of that treaty. Ambiguity in the map and treaty resulted
Arrowhead region being disputed, and previous
negotiations had not resolved the question. The treaty had the border
pass through Long Lake, but did not state that lake's location.
However, the map showed the lake flowing into Lake Superior near Isle
Royale, which is consistent with the Pigeon River route.
The British, however, had previously taken the position that the
border should leave Lake Superior at Fond du Lac (the "head of the
lake") in modern Duluth, Minnesota, proceed up the Saint Louis and
Embarrass rivers, across the height of land, and down Pike River and
Lake Vermilion to the Rainy River.
To counter this western route, the U.S. advocated for an eastern
route, used by early French explorer
Jacques de Noyon
Jacques de Noyon in 1688, and the
later a well-used fur traders' route after 1802. This way headed north
from the lake at the site of Fort William up the Kaministiquia and Dog
Rivers to Cold Water Lake, crossed the divide by Prairie Portage to
Height of Land Lake, then went west by way of the Savanne, Pickerel,
and Maligne rivers to Lake La Croix, where it joined the present
The Mitchell map had shown both of those routes, and also showed the
"Long Lake" route between them. Long Lake was thought to be the
Pigeon River (despite the absence of a lake at its mouth).[a]
The traditional traders' route left the Lake at
Grand Portage and went
overland to the Pigeon, up that river and a tributary across the
Height of Land Portage, and thence down tributaries of the Rainy River
to Lac La Croix, Rainy Lake and River, and Lake of the Woods. This is
finally the route the treaty designated as the border.
The treaty clarified the channel that the border would follow between
Lake Huron and Lake Superior, awarding Sugar Island to the U.S.
Another clarification made in this treaty resulted in clarifying the
anomaly of the Northwest Angle. Again, due to errors on the Mitchell
Map, Treaty of Paris reads "... through the
Lake of the Woods
Lake of the Woods to the
most northwesternmost point thereof, and from thence on a due west
course to the river Mississippi ..." In fact, a course due west from
Lake of the Woods
Lake of the Woods never intersects the Mississippi. The
Anglo-American Convention of 1818
Anglo-American Convention of 1818 defined the boundary about Lake of
the Woods to the Rocky Mountains.
This 1842 treaty reaffirmed the border and further defined it by
modifying the border definition to instead read as:
... at the Chaudiere Falls, from which the Commissioners traced the
line to the most northwestern point of the Lake of the Woods, thence,
along the said line to the said most northwestern point, being in
latitude 49°23′55″ north, and in longitude 95°14′38″ west
from the Observatory at Greenwich; thence, according to existing
treaties, due south to its intersection with the 49th parallel of
north latitude, and along that parallel to the
Rocky Mountains ...
Webster–Ashburton Treaty failed to deal with the Oregon
question, although the issue was discussed in negotiations.
Article 10 of the
Webster–Ashburton Treaty identified seven crimes
subject to extradition: "murder, or assault with intent to commit
murder, or piracy, or arson, or robbery, or forgery, or the utterance
of forged paper." It did not include slave revolt or mutiny. In
addition, the United States did not press for the return or
extradition of an estimated 12,000 fugitive slaves who had reached
While agreeing to call for a final end to the slave trade on the high
seas, Webster and Ashburton agreed to pass over the
Creole case of
1841 in the Caribbean, which was then in contention. In November 1841,
a slave revolt on the American brig Creole, part of the coastwise
slave trade, had forced the ship to Nassau. Bahama officials
eventually emancipated all 128 slaves who chose to stay in Nassau, as
Britain had abolished slavery in its colonies, effective in 1834.
The U.S. initially demanded return of the slaves, then compensation. A
settlement was made in 1855 as part of a much larger claims treaty of
1853, covering claims by both nations to 1814.
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Maine boundary dispute that led to the 1842 Webster–Ashburton Treaty
As a result of the Webster–Ashburton Treaty, the United States ceded
5,000 square miles (13,000 km2) of disputed territory along the
Maine border, including the Halifax–Quebec Route, but kept 7,000
square miles (18,000 km2) of the disputed wilderness. In
addition, the United States received 6,500 square miles
(17,000 km2) of land along the Minnesota–Canada border, which
included the Mesabi Range. Shortly after ratification of the
Webster–Ashburton treaty, the
Ojibwa nations about the south shore
of Lake Superior ceded land to the United States in the Treaty of La
Pointe. However, the news of the ratification of the international
treaty did not reach either of the parties negotiating the land
Grand Portage Band was mistakenly omitted from the Ojibwe
treaty council. In addition, the
Grand Portage Band was misinformed on
the details of the Treaty of Paris; they believed that the border
passed through the center of Lake Superior to the Saint Louis River,
Isle Royale and their band in British territory. The
Treaty of Paris specifically notes
Isle Royale as in the territories
of the United States. Consequently, the
Isle Royale Agreement was
signed between the United States and the
Grand Portage Band in 1844 as
an adhesion to the Treaty of La Pointe, with other
reaffirming the treaty.
Ten months of negotiations for the treaty were held largely at the
Ashburton House, home of the British legation on Lafayette Square in
Washington, D.C. The house has been designated a U.S. National
To make the controversial treaty more popular in the United States,
Webster released a map of the Maine–Canada border, which he claimed
Benjamin Franklin had drawn. It showed contested areas largely
resolved in favor of the United States.
List of treaties
History of Canada–United States border agreements through 1908
Timeline of United States diplomatic history
Estcourt Station, Maine
Oregon boundary dispute
Slave Trade Acts
Treaty of 1818
^ On the La Vérendrye Map, series of lakes are shown, of which "Lac
de Sesakinaga" (Saganaga Lake), a Height of Land, "Lac Plat", "Lac
Grand Portage are shown in relative equidistance from each
other, thus alluding to Mountain Lake or Arrow Lake as "Lac Long", all
long lakes on the Pigeon River route.
^ a b c Carroll (2001).
^ "Decision of the Arbiter, January 1831". Retrieved 26 June
^ Lass (1980), pp. 1, 11, 37.
^ Lass (1980), pp. 37–39, 49.
^ Vogel & Stanley (1992), pp. E-12, E-13.
^ Lass (1980), pp. 37–39, 44.
^ Lass (1980), p. 37.
^ "Webster–Ashburton Treaty, Art. 2". Yale Law School. 1842.
Archived from the original on August 25, 2006. Retrieved September 18,
^ a b Jones (1975a), pp. 28–50.
^ a b Kennedy, Bailey & Cohen (2006), pp. 374, 375.
Works cited and further reading
Carroll, Francis M. (March 1997). "The Passionate Canadians: The
Historical Debate about the Eastern Canadian–American Boundary". New
England Quarterly. . 70 (1): 83–101. JSTOR 366528.
——— (2001). A Good and Wise Measure: The Search for the
Canadian–American Boundary, 1783–1842. University of Toronto
Press. (the standard scholarly history)
——— (2003). "Drawing the Line". Beaver. 83 (4): 19–25.
Corey, Albert B. (1941). The Crisis of 1830–1842 in
Jones, Howard (March 1975a). "The Peculiar Institution and National
Honor: The Case of the Creole Slave Revolt". Civil War History. 21
(1): 28–50. doi:10.1353/cwh.1975.0036.
——— (December 1975b). "Anglophobia and the Aroostook War". New
England Quarterly. 48 (4): 519–539. JSTOR 364636.
——— (1977). To the Webster–Ashburton Treaty: A Study in
Anglo-American Relations, 1783–1843.
Jones, Wilbur Devereux (February 1956). "The Influence of Slavery on
the Webster–Ashburton Negotiations". Journal of Southern History. 22
(1): 48–58. JSTOR 2955259.
Kennedy, David M.; Bailey, Thomas Andrew & Cohen, Lizabeth (2006).
The American Pageant (13th ed.). Boston: Houghton Mifflin.
ISBN 0618479279. OCLC 846067545.
Lass, William E. (1980). Minnesota's Boundary with Canada. St. Paul,
MN: Minnesota Historical Society. ISBN 0-87351-153-0.
LeDuc, Thomas (December 1964). "The
Webster–Ashburton Treaty and the
Minnesota Iron Ranges". Journal of American History. 51 (3):
476–481. JSTOR 1894897. (shows the value of the iron
range was not known when the treaty was drawn)
Merk, Frederick (December 1956). "The Oregon Question in the
Webster–Ashburton Negotiations". Mississippi Valley Historical
Review. 43 (3): 379–404. JSTOR 1893529.
Remini, Robert (1997). Daniel Webster. pp. 535–64.
Vogel, Robert C. & Stanley, David G. (1992). "Portage Trails in
Minnesota, 1630s–1870s" (PDF) (Multiple Property Documentation
Form). National Park Service. Retrieved May 13, 2008.
The Maine Council (1904). Historical Sketch Roster of Commissioned
Officers and Enlisted Men Called Into Service for the Protection of
the Northeastern Frontier of Maine from February to May 1839. Augusta,
ME: Kennebec Journal Print. pp. 4–5. Retrieved October 15, 2007
– via Google Books.
Text of the
Webster–Ashburton Treaty (The Avalon Project at Yale Law
Webster–Ashburton Treaty (U.S. Department of State)
Franklin Map Possibly Forged