The facts gathered by the Whipple Expedition showed that a railroad to the Pacific Ocean along the 35th parallel was feasible. The first step
toward building the railroad was building a wagon road along which people and supplies could be moved. An expedition under the leadership of
Edward Fitzgerald Beale, Superintendent
of Indian Affairs in California, a man who had a long acquaintance with California and travel between there and the east coast, was
organized. It had a two-fold purpose: to survey a wagon road from Fort Defiance, New Mexico, to the Colorado River and to test
the efficacy of camels as a means of military transport in the deserts of the American Southwest. As the expedition moved across the
desert, it not only surveyed a possible route, but left wagon tracks and campsites that wagon trains could use in the immediate future,
before any official road building commenced (Sherer 1994:65-67).
Although Beale had his men light fire signals in the mountains overlooking the Colorado Mountains overlooking the river to tell the Mojaves
he was coming, his men held themselves prepared to fight when they arrived on October 18, 1857, and camped on the riverside. The Mojaves, who
regarded the establishment of a wagon road as a fulfillment of the agreement made with
that a trade route be established through their territory, made no move to stop them as they passed through Mojave territory and crossed
the river on October 19, except that the Mojave blocked them from going downriver. On October 20, the river crossing successfully completed,
the Mojave came into Beale's camp to trade (Sherer 1994:68-69).
Beale's expedition left none of the warm memories with the Mojaves that Whipple's expedition had. Mojave elder Frances Stillman commented
that the Mojave wanted to be friends, but like
before him Beale wanted nothing to do with them. He "came right in and looked like he owned the place, and didn't bother to talk to
anybody, or ask if he might cross or anything. That's what our people didn't like about Beale. He acted as though he owned the whole world" and
the expedition crossed "right in the middle of their land and their river" (Stillman 1989, cited in Sherer 1994:69).
Beale took his expedition as far west as Tejon, let it rest for several months, and then headed back to Fort Defiance in early 1858. In
the meantime, several circumstances made the Mojaves uncertain about the good intentions of the United States. War was brewing between
the United States and the Utah Territory, which had been settled ten years earlier by members of the Church of Latter-Day Saints, popularly
known as Mormons. Both the U.S. War Department and the Mormons saw control of the lower Colorado River as an important military advantage,
and soon the War Department had word that the Mormons had sent men to infiltrate the Mojaves, spreading alarm and suspicion. The War Department
was principally represented in the area by the temporary commander of Fort Yuma, Lt. William A. Winder (Sherer 1994:71-72, 74).
With war clouds gathering, there was considerable interest in the question of how far upstream the Colorado River was navigable, a question
best solved by sending a steamboat up the river to find out. As it happened, there was a boat in the vicinity that could be used for the
purposes, the General Jessup, owned by Captain George Alonzo Johnson, which was used to make trips up the river as far as Fort Yuma. When,
under orders from the Secretary of War, Lt. Joseph C. Ives, earlier with the Whipple Expedition, arrived at the mouth of the
with the makings of a smaller steamboat, the Explorer, that needed to be put together in order for Ives to take it up the Colorado River
to see if it were navigable, Johnson offered to take the General Jessup up the river at once to explore it, and requested a detachment
of troops for protection. Winder assigned a detachment under Lt. James A. White to accompany Johnson and assigned them the task of finding
out the attitude of the Mojaves. Beaver trapper
also accompanied the detachment. Captain Johnson took his big steamboat all the way up the river to Cottonwood Island, thus proving that
the Colorado River was navigable this far, and then turned back, and on January 22, 1858, anchored it at the place on the river's eastern
bank from which Beale's expedition had crossed the river earlier in the fall. The Mojaves, whom the Mormons had succeeded in alarming about
the intentions of the United States, met the boat's crew with friendliness, although they found the fact that their land could be invaded
via the river upsetting. Lt. White assured them of the government's good intentions toward them, and, by the time the boat anchored, felt
reasonably sure they would side with the United States should any armed conflict with the Mormons arise (Sherer 1994:72-75).
The Mojaves' suspicions were raised again when Beale's expedition arrived at the crossing place on the western side later the same
day. Although a happenstance, the coincident arrivals appeared to have been arranged beforehand (1994:75).
The General Jessup ferried Beale's men and their baggage across the river, and then returned to the river mouth, 350 miles to the
south. Beale, upon the completion of his expedition, ended his report with the recommendation that a military post be established
where the wagon road he had been surveying crossed the river to protect emigrant trains from the Mojave (1994:77-78).