William Guerrier was a businessman and Cheyenne

Cheyenne

Cheyenne are a Native American people of the Great Plains, who are of the Algonquian language family. The Cheyenne Nation is composed of two united tribes, the Só'taeo'o and the Tsétsêhéstâhese .The Cheyenne are thought to have branched off other tribes of Algonquian stock inhabiting lands...

 interpretor on the Santa Fe Trail

Santa Fe Trail

The Santa Fe Trail was a 19th-century transportation route through central North America that connected Missouri with Santa Fe, New Mexico. Pioneered in 1822 by William Becknell, it served as a vital commercial and military highway until the introduction of the railroad to Santa Fe in 1880...

 and Oregon Trail

Oregon Trail

The Oregon Trail is a historic east-west wagon route that connected the Missouri River to valleys in Oregon and locations in between.After 1840 steam-powered riverboats and steamboats traversing up and down the Ohio, Mississippi and Missouri rivers sped settlement and development in the flat...

 and is believed to be the first rancher in Wyoming

Wyoming

Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...

.

Guerrier was born in St. Louis, Missouri

St. Louis, Missouri

St. Louis is an independent city on the eastern border of Missouri, United States. With a population of 319,294, it was the 58th-largest U.S. city at the 2010 U.S. Census. The Greater St...

. After moving west, he married a Cheyenne

Cheyenne

Cheyenne are a Native American people of the Great Plains, who are of the Algonquian language family. The Cheyenne Nation is composed of two united tribes, the Só'taeo'o and the Tsétsêhéstâhese .The Cheyenne are thought to have branched off other tribes of Algonquian stock inhabiting lands...

 woman and had a son Edmund Guerrier

Edmund Guerrier

Edmund Gasseau Choteau Le Guerrier , of French and Cheyenne parentage, was a survivor of the Sand Creek massacre in 1864. He was an interpreter for the U.S...

 in 1840.

In 1844 he began working for William Bent

William Bent

William Wells Bent was a frontier trapper, trader, and rancher in the American West who mediated among the Cheyenne Nation, other Native American tribes and the expanding United States. With his brothers, Bent established a trade business along the Santa Fe Trail. In the early 1830s Bent built an...

 at Fort Bent on the Santa Fe Trail

Santa Fe Trail

The Santa Fe Trail was a 19th-century transportation route through central North America that connected Missouri with Santa Fe, New Mexico. Pioneered in 1822 by William Becknell, it served as a vital commercial and military highway until the introduction of the railroad to Santa Fe in 1880...

. In 1845 he acted as interpretor in a meeting near the fort to create a peace treaty between the Cheyenne

Cheyenne

Cheyenne are a Native American people of the Great Plains, who are of the Algonquian language family. The Cheyenne Nation is composed of two united tribes, the Só'taeo'o and the Tsétsêhéstâhese .The Cheyenne are thought to have branched off other tribes of Algonquian stock inhabiting lands...

 and the Delaware (tribe) which had been forced west by the Indian Removal Act

Indian Removal Act

The Indian Removal Act was signed into law by President Andrew Jackson on May 28, 1830.The Removal Act was strongly supported in the South, where states were eager to gain access to lands inhabited by the Five Civilized Tribes. In particular, Georgia, the largest state at that time, was involved in...

.

In 1848 he struck up a business arrangement with Seth E. Ward called Ward and Gurrier.

In 1849 his wife died of cholera

Cholera

Cholera is an infection of the small intestine that is caused by the bacterium Vibrio cholerae. The main symptoms are profuse watery diarrhea and vomiting. Transmission occurs primarily by drinking or eating water or food that has been contaminated by the diarrhea of an infected person or the feces...

. Guerrier sent his son back East to St. Louis University while he and Ward continued their trading business with settlers.

Ward and Guerrier got the exclusive sutler

Sutler

A sutler or victualer is a civilian merchant who sells provisions to an army in the field, in camp or in quarters. The sutler sold wares from the back of a wagon or a temporary tent, allowing them to travel along with an army or to remote military outposts...

 contract for Fort Laramie in 1851. In 1852 they moved to a few miles to Register Cliff

Register Cliff

Register Cliff is a sandstone cliff and featured key navigational landmark prominently listed in the 19th century guidebooks about the Oregon Trail, and a place where many emigrants chiseled the names of their families on the soft stones of the cliff it was one of the key checkpoint landmarks for...

. Their practice of trading goods for the worn oxen of settlers is sometimes said to make them the first ranchers in Wyoming.

He died when sparks from his pipe hit an open gunpowder

Gunpowder

Gunpowder, also known since in the late 19th century as black powder, was the first chemical explosive and the only one known until the mid 1800s. It is a mixture of sulfur, charcoal, and potassium nitrate - with the sulfur and charcoal acting as fuels, while the saltpeter works as an oxidizer...

keg.