Repatriation of David Thompson’s Map of Western North America 84° West to the Pacific Ocean

In 2003, while reading ‘Early Fur Trader on the Northern Plains’ by Wood & Thiessen, an obscure, very small, image of Thompson’s 1797/98 trek to the Mandan Villages was present in the book. Already familiar with Thompson’s manuscript map located at the Archives of Ontario I did not recognise the small image and noted the archival reference, National Archives, Kew, England (TNA). I returned to the image in 2005 and soon realized that I had “rediscovered” another Thompson map. The map held at the TNA in fact was a later version of the manuscript map that Thompson produced for the North West Company in June of 1814, and the manuscript map that currently resides in the Archives of Ontario.

The “rediscovery” term should not surprise anyone as the map was first discovered by Victor Hopgood tucked away in the National Archives, UK. In terms of availability, the map was too far away for Canadian researchers to pay any real attention to it or study for that matter. This was perhaps the single biggest reason that Thompson’s manuscript map at the TNA has remained elusive and therefore forgotten. I should be clear in that this is not another Elgin Marble story and the map was not taken or stolen from Canada. In fact it was sold to the British Foreign Office by Thompson in 1844 and was eventually housed it in the Public Record Office. The Public Record Office would later be renamed The National Archives. Having said that I did contemplate a manner in which we could have the map repatriated and after some time gave up on the idea of physically repatriating the real map and became interested in creating a digital copy of the map.

Not long after this, in 2010, my Colleague David Malaher and I were approached by the CEO of modern North West Company (NWC) about creating a replica of the map for the company meeting room. After putting into practice ideas based on work that I already did in the surveying and mapping industry, I put a plan together and created a true scale image based on 10 images that I had already ordered of the map just the year before. The result exceeded our expectations and although did not create a copy good enough for intense study, it did create a map that was fully readable.

With such good results from this effort, I began creating a plan to create a high resolution image for replication of the map, once again, at true scale. The creation of the replica this time had to fulfill 2 primary goals in order to justify the money and work that would be required to accomplish the digital repatriation. These 2 goals were 1) Creation of an exact replica and 2) the donation of the acquired images and the replica map to an academic institution.

The image created for the North West Company was a benchmark of sorts and it proved that a detailed effort could succeed. Given the resolution required I calculated that rather than 10 images, I would have to have 176 images shot of the map at 600 dpi. Following a concerted effort to raise funds to purchase the images, an order was placed at the TNA and 4 weeks later the images arrives at my doorstep. Ultimately (after 1280 hours, 70GB in imagery and 20,400 reference points) the images were painstakingly stitched back together in a modern geographic information software package.

In the midst of doing the geographic work came our first research trip to Kew; I had brought with me a competed portion of the map for comparison to the real map. Once again the result more than exceeded both David’s and my expectations… you could barely tell the two portion apart. Nearing the end of the geographic work, David Malaher had, through great effort, found the Elizabeth Dafoe Library, University of Manitoba, a grateful recipient of the original images and replica map.

David Malaher with the map displayed at the Elizabeth Dafoe Library, University of Manitoba

In a letter to Sir James Alexander on 9 May 1845, Thompson expressed his dismay and fear that all of his maps, surveys, astronomical observations, drawings of the countries, sketches and measurements of the mountains would “all soon to perish into oblivion.” Both David Malaher and I hope that placing the map and its associated images here in Canada, at the University of Manitoba will ensure that his work never perishes and that David Thompson’s Manuscript Map will no longer be hidden from view and forgotten.