The Mackay and Evans Map

James Mackay and John Thomas Evans traveled up the Missouri River under the Spanish Flag in 1795. Their instructions from the Spanish governor were similar to Jefferson’s instructions to Meriwether Lewis. They were to map their way upriver to the source and find the Pacific Ocean, collect specimens of new plants and animals, and make trade and security agreements with the Native American tribes they met. Their expedition was not successful, but they brought back new geographical information about the part of the west which is nodern-day Nebraska.

In 1797, Mackay Evans drew maps in their journals of the Missouri River from St. Louis to Three Forks, Montana. View an example detail from this map on the Yale University Beniecke Library Web site.

However, today few Americans recognize their names. The reasons for this are many and complex. Their original plan was to travel for six years, but they had to cut the journey short because of resistance from the Sioux Indians. In giving presents to the Indians to compete with the British for trade rights, Mackay depleted his store of trade goods quickly. The corps was undermanned when groups of men had to accompany a hunting party to help the Indians and the travelers survive a winter, and one man was left in charge of a new trading post. Interpreters were not as familiar with Indian languages as expected. Finally, additional assistance from the Spanish government was slow to come.

Although they failed to reach the Pacific Ocean, Mackay and Evans, with their map and their experience, set the stage for the success of Lewis and Clark. Lewis traveled to St. Louis with John Hay and Nicholas Jarrot, and they asked the Lieutenant Governor DeLassus and Surveyor General André Soulard for assistance. Soulard secretly allowed Lewis to copy some of the map of the Missouri River made by James Mackay in 1897-98, but was very fearful of punishment if word got out he allowed this. Lewis became aware that Mackay himself lived some two days up the Missouri River in St. Andre, but Lewis did not have permission to travel in Spanish territory. So covert methods were employed so Lewis and Clark could get the information they needed. Private Joseph Fields had been sent upriver to Griffith’s farm for produce several times. New evidence (Danisi and Wood, 2004) suggests that Fields probably left for St. Andre on January 7, 1804. Mackay was witnessing and signing documents at St. Andre and Marais des Lairds upriver from Camp DuBois, and surveying some land at Portage des Sioux. Mackay came down to Camp DuBois and spent time, probably overnight, with Clark to go over his map. Clark did not mention this visit in his field notes, but by January 21, he was adding details about the distances to the Mandans, the Rockies, and the Pacific to his own map.
View a detail from Soulard's 1795 map on the Beinecke Library site at Yale.

Mackay’s map of 1797 became known as "The Indian Office Map" because it was found there after many old maps had been dispersed or lost. Both Mackay and Evans drew maps of their journey, and Evans collected information from Native Americans for the westernmost portions of his maps. All of these sources went into the final map. Recent analysis shows that that stylistic details of the 1797 map are identical to other known Mackay Maps, arguing that this map was drawn by Mackay, possibly with assistance from Andre Soulard.