History of Mormonism, the LDS Church recently was driven from their homes by a mob in Illinois, and they camped near Omaha Nebraska. They repeatedly asked the government for federal aid, but was denied. Brigham Young sent Elder Jesse Little to Washington D.C. to ask for government assistance. Jesse arrived eight days after Congress declared war on Mexico. After some debating, the President allowed for a few hundred men to be recruited. Around 500 were recruited, and formed the Mormon Battalion. Women required for laundry were recruited as well. The men were able to get their uniforms free of charge, and a $42 advance pay. The money went towards the saints to get food and necessities and preparing for the trip to what is now known as Utah.
The Mormon Battalion was split into five companies.
Soon after the Battalion was under command of James Allen, he became ill and later died. Soon after, Andrew Jackson Smith became the commanding officer. He and the doctor made life miserable for the Battalion. They weren't used to the vigorous marching, nor the medicine at the time (the elders counseled with members of the Battalion to not use the medicine from the Army, maybe because it had to do with consuming alcohol)
Later when the Battalion arrived in Santa Fe, much to their relief, Smith was replaced by Phillip Cooke, and they soon learned to respect him well. All the women and many sick men were sent to Pueblo.
Cooke and the Battalion marched into some of the most difficult terrain in North America. They had help from a guide, Jean Baptiste, who was as an infant carried by Sacajawea during the Lewis and Clark Expedition.
Along the way, the men helped some local tribes, and some of the locals taught the men some irrigation techniques that would later be critical and beneficial when the saints moved to Utah.
The Battalion never participated in a real battle, besides fighting some bulls and guarding a tribe. 22 men died from disease or natural causes.
After their year was up, some decided to re-enlist, and most decided to head home. On the way, in California, Some of the men discovered gold, which would result in the 1849 gold rush.
The Mormon Battalion brought home around $30,000 in salaries and another $17,000 worth of gold, which helped them significantly in the trip to Utah.