But although facile games of "what if?" often are entertaining, they seldom teach us what really happened. Instead, let us look closely at the elements of the captains' plan, and the related events that actually ensued, for they reflect Jefferson's policies toward Indian nations.
The captains' scheme was grounded in a decision that defied their commander-in-chief's orders — and for which they might well have been court-martialed: They would not only divide their unit into two contingents, but ultimately into five widely separated, equally indefensible details. It placed the entire expedition at risk of disaster.
Captain Lewis would try out the shortcut from Travelers' Rest to the Great Falls of the Missouri via the Blackfoot River, which Indians had mentioned to the captains several times.2 Then he and three of his men would proceed up Maria's River to ascertain whether its sources lay at or above fifty degrees north latitude, information that could establish a clear geographical delineation of Louisiana's northern boundary. The story of his journey into the heart of Blackfeet Indian country, its one big disappointment, and its long-term tragic consequences, is well known. Had it worked out as Lewis hoped, it might have simplified U.S.-British relations for at least the next decade — until the international boundary was amicably defined, in large part, after the War of 1812.
Second, Captain Clark would return to the Three Forks of the Missouri via Camp Fortunate, and send Sergeant Ordway with eleven men in the canoes back to the Great Falls. He, with nine men and forty-nine horses, plus York, Sacagawea and her child, would then proceed overland to the Yellowstone River, build dugout canoes, and meet Lewis and his Missouri River contingent at the confluence of the two rivers around the first of August. (They almost made it on schedule, and that was perhaps the best outcome of all.)3
It would have been a bonus had Clark also learned enough about the geography of the Yellowstone River to prove that this "delightfull river" arose near the "North river" (the Rio Grande) in Spanish America. Rumor and conjecture led Lewis and Clark to theorize that the Yellowstone "also most probably has it's westerly sources connected with [those of] the Multnomah [today, the Willamette] and . . . the main Southerly branch of Lewis's river [the Snake], while it's Easterly branches head with those of Clark's R. [the Clark's Fork of the Yellowstone], the Bighorn and River Platte, and may be said to water the middle portion of the Rocky Mountains from N W to S. E. for several hundred miles." But Clark did''t get to see the Yellowstone above the Big Bend, nor did he meet any Crow Indians who might have shared their knowledge of what its upper reaches were really like, so these "facts" added up to hearsay spiced with guesswork, and their theory was still just a bird in the bush.4
Each party also had to retrieve the precious supplies that had been cached at Camp Fortunate, White Bear Islands, and the mouth of the Marias--which clearly suggests this whole scheme was nascent before the Corps left the Marias in June of 1805.
The boldest plan of all, however, was basically consistent with the President's instruction to Lewis: "If a few of their influential chiefs, within practicable distance, wish to visit us, arrange such a visit with them . . . at the public expense.5 The most influential would be the chiefs of the Sioux, who controlled the conduit to the existing and potential trading centers on the upper Missouri River, and they were certainly within practicable distance. If this plan succeeded, the chiefs would be impressed by American strength and wealth, would go home and persuade their people and their neighbors to live in peace, renounce their old British loyalties, welcome American trading posts up and down the Missouri, and become full-fledged partners in the grand enterprise of extending the American nation all the way to the Pacific Coast.
The leading figure in this scenario was a Canadian fur trader named Hugh Heney.
1. Even then, in February of 1806, President Jefferson was reporting to Congress on the course of the expedition, and reminding its members that Lewis's objective was to cross the "highlands by the shortest portage, to seek the best water communication thence to the Pacific ocean." Donald Jackson, ed., Letters of the Lewis and Clark Expedition with Related Documents, 1783–1854 (2nd ed., Urbana: University of Illinois Press, 1978), 1:299.
2. In a letter he wrote to President Jefferson from Fort Mandan in April of 1805, he advised, "On our return we shal probably pass down the yellow stone river, which from Indian information, waters one of the fairest portions of this continent." Yet they would leave one pirogue and a cache of supplies at the mouth of the Marias River, and the other pirogue and two caches at the Great Falls, which indicates that the information gained from Indians the previous winter had set the captains to thinking about splitting the Corps of Discovery into two contingents on their return trip. Ibid., 1:234.
3. Clark arrived at the mouth of the Yellowstone at 8:00 on the morning of the third, but mosquitos drove him on down the Missouri; Lewis caught up with him at noon on the twelfth, about 130 miles downriver.
4. The theory is in Clark's journal entry for August 3, 1806, but it's in Lewis's hand. Since Lewis didn't catch up with Clark until August 12, they must have discussed the probabilities before Lewis inserted their conclusions in Clark's journal. Moulton, Journals, 8:277. See also John L Allen, Lewis and Clark and the Image of the American Northwest (New York: Dover, 1975), 359–62. "The Indians"--probably the Hidatsas--also told them that "a good road passes up this river to it's extreem source from whence it is but a short distance to the Spanish settlements," and further related that there was "a considerable fall" on the upper Yellowstone, in the mountains. The second point is a fact, while the first is an exaggeration: It's more than 600 miles--perhaps three weeks' travel--from the headwaters of the Yellowstone to Santa Fe.
5. Jackson, Letters, 1:64.