William Becknell opens a trade route between the Missouri River and the Mexican provincial capital of Santa Fe.
Texas declares independence from Mexico. Four days later, the siege on the Alamo ends and San Antonio falls to Mexican forces. Texas wins its final battle for independence on April 21, 1836.
A border dispute in Oregon Territory proves to be a major issue in the American presidential race. James K. Polk wins the election by appealing to those who want more land.
U.S. Congress approves annexing Texas to the United States. James K. Polk becomes president of the United States four days later and pledges to protect Americans settling in Oregon and Texas.
Brigham Young and the Twelve instruct Jesse C. Little to travel to Washington D.C. to seek assistance from the federal government to fund the move west.
Brigham Young leads several wagons out of Nauvoo into Iowa Territory, marking the beginning of a mass migration west.
The ship Brooklyn sets sail from New York bound for California. On board are 239 Mormon colonists under the leadership of Samuel Brannan.
Mormon colonists leave Mississippi hoping to catch up to Brigham Young at the Platte River.
The United States declares war on Mexico.
Jesse C. Little writes a letter to President James K. Polk seeking assistance from the federal government for the move west.
President James K. Polk authorizes 500 Mormons to be enlisted to help the United States in its war with Mexico.
Captain James Allen and an escort of soldiers arrive at Mount Pisgah, Iowa, to begin enlisting a Mormon Battalion.
Most of the Mormon Battalion are officially enlisted into the U.S. Army. James Allen assumes command as a lieutenant colonel. The first four companies depart Council Bluffs on July 20, 1846. At least 34 women and 44 children travel with the battalion.
The fifth company, Company E, leaves Council Bluffs for Fort Leavenworth.
Samuel Brannan and Mormon colonists aboard the ship Brooklyn arrive in Yerba Buena (later renamed San Francisco).
The Mormon Battalion arrives at Fort Leavenworth and spends two weeks drilling and resupplying. James Allen dies from illness at Fort Leavenworth on August 23. Lieutenant Andrew Jackson Smith assumes command of the Mormon Battalion on August 30, 1846.
Mississippi Company under John Brown realizes that they are ahead of Brigham Young on the trail. They winter at Fort Pueblo in present-day Colorado.
General Stephen W. Kearny captures Santa Fe for the United States.
Lieutenant Smith orders a sick detachment to Bent’s Fort. They continue to Fort Pueblo. A second sick detachment leaves Santa Fe in mid-October, and the last leaves the main body of soldiers in mid-November. The groups winter together in Fort Pueblo.
Lieutenant Smith and a contingent of the Mormon Battalion arrive at Santa Fe. Others arrive over the next three days.
Lieutenant Colonel Philip St. George Cooke assumes command of the battalion, and they leave Santa Fe on October 19, 1846.
The Mormon Battalion leaves the Rio Grande and begins blazing a new wagon road to California.
Battalion members encounter wild bulls, resulting in “the battle of the bulls.” This is the only time the battalion members are ordered to use their weapons in self-defense.
The battalion reaches Tucson and nearly engages in battle with a Mexican garrison.
The Mormon Battalion reaches the Pima villages on the Gila River.
Colonel John C. Frémont and General Andres Pico sign the Treaty of Cahuenga, ending military conflict in California.
The Mormon Battalion arrives in San Diego. After a few days’ rest, they march to Mission San Luis Rey.
Company B is assigned garrison duty in San Diego. All other companies march to Los Angeles, except about three dozen ill soldiers who remain at Mission San Luis Rey.
Colonel Cooke orders Mormon soldiers to construct Fort Moore in Los Angeles. It is completed on July 4, 1847.
Mississippi Saints and battalion soldiers leave Fort Pueblo to continue west. They arrive in the Salt Lake Valley five days after Brigham Young’s vanguard company.
Intent on a court-martial of Colonel John C. Frémont for insubordination, General Kearny leaves Monterey with a company of 64 soldiers, including Colonel Cooke and 15 members of the battalion. Jefferson Hunt assumes command in Los Angeles until the battalion’s discharge.
The Mormon Battalion is discharged from U.S. military service at Fort Moore in Los Angeles by Lieutenant Andrew Jackson Smith, former commander of the battalion. Four days later, about 80 battalion soldiers known as the “Mormon Volunteers” reenlist in the army.
Mormon Battalion members who have not reenlisted travel north on the El Camino Real or along the Sierra Nevada foothills to northern California.
Brigham Young enters the Salt Lake Valley.
The 15 Mormon Battalion soldiers with General Kearny arrive at Fort Leavenworth. Upon discharge, they travel back to Winter Quarters.
Battalion veterans leave Sutter’s Fort for the Salt Lake Valley. Along the way, they learn that there are few provisions waiting for them. Some return to the Sacramento Valley and find work. Others push ahead.
Members of the battalion who did not find their families in Utah travel further east, arriving at Winter Quarters in December 1847.
John Sutter’s partner, James Marshall, discovers gold at Coloma on the American River. Six Mormon Battalion veterans are present for the discovery.
The Treaty of Guadalupe Hidalgo ends the Mexican-American War.
The reenlisted “Mormon Volunteers” are discharged. A few of them, under the leadership of Henry G. Boyle, travel the Spanish Trail east and then turn north, creating a wagon road between Salt Lake City and Los Angeles.
Three Mormon scouts of the Holmes–Thompson company are murdered by Indians while traveling east through the Sierras at a site later named Tragedy Spring.
The Holmes–Thompson company, comprising mostly Mormon Battalion veterans, leaves for the Salt Lake Valley from central California and blazes the Mormon-Carson Pass Emigrant Trail over the Sierra Nevada.
Companies of men, women, and children who had sailed on the ship Brooklyn join Mormon Battalion veterans on their journey east from California to the Salt Lake Valley using the newly opened Carson route. They arrive in September and October 1848.