Another contributing cause to the war, not generally understood, but of some weight, was the Mormons. At a council held at about this time at the lodge of Ka-mi-akin, then encamped at Sire-co-e, there was present a Bannock Indian who claimed that he was sent out by the Mormons of Salt Lake to arouse the Indians against the whites. He said that, far to the east, in a desert country, there lived a white race that controlled the sun; and that he had lived among them and talked with them. These people had sent him there to tell about them and that they could strike dead anybody at any distance. They made powder and muskets and were friends of the Indians, while the Americans were their enemies. He said they wanted the Indians to kill all the whites in their land, and that they would furnish arms and ammunition.

That the Mormons did sell the Indians the means of making war, there can be little doubt, for Capt. B. F. Shaw found among the Walla Wallas and Cay-uses, muskets and powder balls with the Mormon brands on them.