The “Mormon War” broke in 1857. . . . ‘l’he aspen leaves were already flashing a brilliant yellow and the chill of autumn was abroad when the little army reached the Green River valley in present western Wyoming. . . . Lot Smith, clever and elusive, captured several of the trains of supplies which were in the rear of the troops. . . .
“The army found itself in a rather hazardous position. With supplies greatly reduced, winter snows already falling, and with one hundred miles of bleak mountains separating them from the Mormon metropolis beside the Great Salt Lake, it was decided to forstall plans of conquest for the present season and establish winter quarters. New supplies in quantity must be had and the nearest source was at Fort Union, New Mexico. To that depot a detachment must be sent for succor. Albert S. Johnston (later killed as a Confederate general in the Civil War) was in command of the United States troops at Fort Bridger. He ordered Captain R. B. Marcy to lead the expedition to New Mexico.”