In 1846, the unsettled area that is now Parker, Colorado, was wild open plains inhabited only by local Indian tribes and passing trappers and traders. The Crosby-Brown Company, also known as the Mississippi Saints, and detachments of the Mormon Battalion of Iowa Volunteers camped along Cherry Creek, on a route first known as the old Trappers Trail and later as the Cherokee Trail. Brigham Young had agreed to meet the Mississippi Saints on the Oregon Trail while traveling with the Advance Pioneer Company, but in July 1846 the group discovered that they had been missed and, as winter approached, traveled on to Pueblo, Colorado. There, under a cottonwood tree, Sarah Emma Kartchner was born, the first Caucasian child born in the unorganized territory. That same year, at the dawn of the Mexican-American War, five hundred Mormon men volunteered in Council Bluffs, Iowa, to serve in the United States Army of the West under General Stephen W. Kearney, and after severe religious persecution they welcomed the chance to move west while defending their country. On the Santa Fe Trail, three sick detachments were sent to Pueblo to winter and recuperate with aid from the Mississippi Saints. They spent nearly a year in Colorado, becoming the first group to establish a religious colony in the West since the eighteenth century. In early May 1847, seventeen members of the Robert Crow and George Therikill families left Pueblo before the rest of the battalion and traveled through present-day Parker on their way to Fort Laramie, Wyoming. They were ultimately among the first pioneers to enter the Valley of the Great Salt Lake with Orson Pratt's Advance Company on 22 July 1847. On 24 May 1847, the sick detachment of the Mormon Battalion received orders and set out to meet Brigham Young's company at Fort Laramie, accompanied by the remaining Mississippi Saints, with a wagon train of sixty wagons, three hundred fifty to three hundred seventy-five people, three hundred cattle, and one hundred horses. After severe thunderstorms and hail forced them to seek shelter, they camped once again on Cherry Creek, where John Taylor Brown was born and is believed to have been the first Caucasian born in what is now Douglas County, Colorado.