Friday, May 3, 2013

The bounds of Oregon Country

Recently, I made a a series of maps of the historical Oregon Country. This was for an online exhibit at the Osoyoos & District Museum, which can be seen here:

The Oregon Country was jointly occupied by the U.S. and Great Britain from 1818, when the two countries signed a treaty formalizing relations after the War of 1812, until 1846, when they divided the Oregon Country along the 49th parallel. In the course of producing these maps, the museum's curator, Ken Favrholdt, and I determined that there was no clear idea of where the Oregon Country ended to the north, and that today Oregon Country is often misrepresented as having ending at 54° 40' north.

What would the actual north bound of Oregon Country have been?

The lands the U.S. and Britain were negotiating over had large regions that were poorly explored (that is, poorly explored by Europeans and by those from back east). Representatives of both countries relied on maps that, the farther north one went, were less and less accurate, as well as being essentially unchecked. When diplomats defined the Oregon Country, they were assuming the maps reflected something more or less accurate.
Hooker and Brown from US Ex. Ex. map of Oregon Country, 1841
One nice illustration of how little knowledge there was is the case of Mounts Hooker and Brown. These two 16,000' peaks were said to lie on either side of Athabasca Pass, the route through the Rockies pioneered by David Thompson in 1811. They appear authoritatively presented on the 1841 map of Oregon Territory by the U.S. Exploratory Expedition, the 1844 map of the Oregon Territory by the French diplomat Eugene Duflot de Mofras, and the 1844 map of North American by John Arrowsmith in London.

And this was only at 52° north. What other unchecked assumptions lay further north?

Even though there were strong sentiments in both Britain and the U.S. that as little as possible of the Oregon Country should be ceded to the other party, the exact bounds of Oregon Country were never well defined. The Treaty text (the Anglo-American Convention of 1818) stipulates that it is the "North West Coast of America, Westward of the Stony Mountains." Let's look at what these words might mean.

Watersheds, latitudes and the crest of the Rockies in Oregon Country
The West bound is pretty clear: it's the Pacific Ocean.

The South bound is pretty clear: it's the 42ndparallel, agreed to be the northern limit of Spanish claims in the 1818 Adams–Onís Treaty.

The East bound relies on there being a feature called the Stony Mountains. Most maps of the period  show the Stony Mountains as a thin band of peaks running north-south, which would have made a precise boundary.

The Arrowsmith map from 1844, showing the Rockies as a single chain
But the reality is that the Rockies are a fairly fat range. In practice, we generally look to the watershed divide to define where "Westward of the Stony Mountains" might begin. But the farther north one goes, the more the watershed divide begins to play with your mind.

South of 52°, it's a simple choice of the Atlantic watershed on one side, and the Pacific watershed on the other. But north of 52° one has to choose between the Atlantic-Arctic divide, which wanders off across the high plains to the northeast, or the Pacific-Arctic divide, which continues to follow the core of the range. Assuming you choose the latter, your next conundrum occurs at about 54° 30', where the Pacific-Arctic divide diverges from the Rockies and heads northwest. At this point, large rivers of the Peace River system are rising west of the crest of the range and flowing through it. Here the range has no meaning as a watershed divide at all.

If we stick by the words of the treaty, we are bound to continue following the crest of the Rockies. So Oregon Country north of 54° 30'  includes some eastward flowing rivers. And indeed, cartographers of the time, if they ever mapped Oregon Country this far north, drew there line as we have, along the crest of the Rockies.

The North bound is the big mystery. The Treaty did not address it, and here we get into territory that was little travelled and little reported.

Nowadays it's not uncommon for a history map to show Oregon Country as ending at  54° 40' north. They either show this as a line drawn from the Pacific Ocean to the Rocky Mountains by the 1824 treaty between the U.S. and Russia, which is wrong, or they show it as the northern limit of American claims, which is right, but in neither case does this mean that Oregon Country ended here.

54° 40' was not a number that meant anything when the Oregon Country was set up in 1818. It arises for the first time six years later when the Americans and the Russians sign the St. Petersburg Convention of 1824. This treaty mentions 54° 40' as a latitude to separate their respective spheres of influence regarding coastal establishments. The wording of the treaty is “there shall not be formed by the citizens of the United States ... any establishment upon the Northwest Coast of America, nor in any of the Islands adjacent, to the north of fifty-four degrees and forty minutes of north latitude ; and that, in the same manner, there shall be none formed by Russian subjects... south of the same parallel.”   

Eugene Duflot de Mofras's map, 1844
Line at 54° 40' on the Duflot de Mofras map
Nonetheless, this begins the practice of cartographers drawing a line at 54° 40' all the way from the coast to the crest of the Stony Mountains, a distance of about 700 km. Some, like Duflot de Mofras in 1844, claim this line merely represents something defined in the treaty, and leave either side of it the same colour.  In other words, there's no implication that this was the end of Oregon.

Map of Oregon Territory, 1841, Wilkes Expedition
Detail of 54° 40' line on Wilkes Expedition map

Others are more ambiguous. The American "Wilkes Expedition" of 1841 produced an authoritative-looking "Map of the Oregon Territory" on which the Oregon Country ended, at 54° 40', with an unlabelled line in the same style as other international boundaries on the map.

Jeremiah Greenleaf, 1840, Brattleboro

American commercial map-makers go further: they colour the land differently on either side of  54° 40', and label the line as  "Boundary of Russian Possessions Settled by Convention in 1824" (Jeremiah Greenleaf, Brattleboro, in 1840) or "Boundary of 1824" (Henry Tanner, Philadelphia, in 1833).
Henry's Tanner's 1833 map of Oregon

From Lawrence J. Burpee, editor, AN HISTORICAL ATLAS OF CANADA, Toronto, Thomas Nelson and Sons, 1927

So the myth grows that the disputed Oregon Country somehow stopped at 54° 40', and in the 20th century you have maps like one from Burpee's Historical Atlas of Canada, 1927, that shows the Oregon boundary running along 54° 40', or this
Denoyer-Geppert 1941 Historical Oregon Country
Denoyer-Geppert 1941 school room map of the Historic Oregon Country, where  54° 40' is labelled both as the treaty line of 1824 and as the limit of American claims. But the yellow colour says something else: that north of 54° 40' is not Oregon Country.
Our question was, how did people on the ground on this side of the Rockies, think of Oregon Country? We decided to resolve this problem by looking to the Hudson's Bay Company. They had an administrative unit here, called the Columbia Department, which represented the scope of fur-trading activities throughout the Oregon Territory. It began at the crest of the Rockies, and it went as far south as the Spanish border; what did they take to be the northern limit of this Department?

Oregon Country as we mapped it
These lands had fallen under HBC control in 1827 when they bought the North West Company and its operations. The north half of what the HBC eventually called the Columbia Department had been called New Caledonia by the NWC. and its northern limits were basically as far north as its northernmost posts, Fort McLeod and Stuart's Lake Fort, could trade. Practically, this was the headwaters of the Nass and Skeena Rivers (which closely parallel each other west of the divide) and the headwaters of the Finlay River (east of the divide; effectively the headwaters of the Peace). These areas, incidentally, are north of 54° 40'.

This being the practical limits of Oregon Country for the fur traders at the time, we decided to use the Nass and Finlay Rivers as our boundary.  Note that these two rivers do not meet at the divide. Their respective headwaters are about 50 km apart, and occur in close proximity to the headwaters of the Stikine, another Pacific river that reaches the coast farther north. A connecting line had to be drawn using the watershed boundaries, first the Finlay-Skeena, then the Stikine-Skeena, then the Nass-Stikine.